Performance information

• GroundBIRD : A CMB polarization experiment with MKID arrays　　　　　　　　　　　　　　　
  Kyungmin Lee; Jihoon Choi; Ricardo Tanausú Génova-Santos; Makoto Hattori; Masashi Hazumi; Shunsuke Honda; Takuji Ikemitsu; Hidesato Ishida; Hikaru Ishitsuka; Yonggil Jo; Kenichi Karatsu; Kenji Kiuchi; Junta Komine; Ryo Koyano; Hiroki Kutsuma; Satoru Mima; Makoto Minowa; Joonhyeok Moon; Makoto Nagai; Taketo Nagasaki; Masato Naruse; Shugo Oguri; Chiko Otani; Michael Peel; Rafael Rebolo; José Alberto Rubiño-Martín; Yutaro Sekimoto; Junya Suzuki; Tohru Taino; Osamu Tajima; Nozomu Tomita; Tomohisa Uchida; Eunil Won; Mitsuhiro Yoshida
  Journal of Low Temperature Physics, Volume：200, Number：5-6, First page：384, Last page：391, Nov. 2020
  GroundBIRD is a ground-based experiment for the precise observation of the
  polarization of the cosmic microwave background (CMB). To achieve high
  sensitivity at large angular scale, we adopt three features in this experiment:
  fast rotation scanning, microwave kinetic inductance detector (MKID) and cold
  optics. The rotation scanning strategy has the advantage to suppress $1/f$
  noise. It also provides a large sky coverage of 40\%, which corresponds to the
  large angular scales of $l \sim 6$. This allows us to constrain the
  tensor-to-scalar ratio by using low $l$ B-mode spectrum. The focal plane
  consists of 7 MKID arrays for two target frequencies, 145 GHz and 220 GHz band.
  There are 161 pixels in total, of which 138 are for 144 GHz and 23 are for 220
  GHz. This array is currently under development and the prototype will soon be
  evaluated in telescope. The GroundBIRD telescope will observe the CMB at the
  Teide observatory. The telescope was moved from Japan to Tenerife and is now
  under test. We present the status and plan of the GroundBIRD experiment.
  Scientific journal
  DOI：https://doi.org/10.1007/s10909-020-02511-5
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  DOI ID：10.1007/s10909-020-02511-5, ISSN：0022-2291, eISSN：1573-7357, arXiv ID：arXiv:2011.07705, SCOPUS ID：85089449833
• Development of embedded STJ for large format array X-ray detector　　　　　　　　　　　　　　　
  Y. Ito; M. Aoyagi; C. Otani; M. Naruse; H. Myoren; T. Taino
  Journal of Physics: Conference Series, Volume：1590, Number：1, Jul. 2020
  We have been developing an embedded superconducting tunnel junction (e-STJ) for a large-format array X-ray detector. Compared with the conventional STJ array, the e-STJ array is suitable for enlarging the detection area effectively because the e-STJ detector utilizes a three-dimensional packaging technology. To investigate the relationship between the fabrication method and the electric characteristics of the e-STJ, we designed and fabricated three types of simplified e-STJ and measured their subgap leakage current in the temperature range from 4.2 K to 0.3 K. We found that the roughness of the embedding hole on the Si substrate and the contact part between the embedded STJ and the side of the embedding hole affected the subgap leakage current.
  Institute of Physics Publishing, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/1590/1/012035
  DOI ID：10.1088/1742-6596/1590/1/012035, ISSN：1742-6596, SCOPUS ID：85090054199
• Superconducting Resonators with Niobium and $${\mathrm{YBa}_{2}\mathrm{Cu}_{3}O_{7-{\delta } } }$$ for Alpha-Particle Detectors
  M. Naruse; T. Ando; Y. Waga; R. Kubota; S. Mima; C. Otani; T. Taino; H. Myoren
  Journal of Low Temperature Physics, Volume：199, Number：3-4, First page：614, Last page：621, May 2020
  Springer Science and Business Media LLC, Scientific journal
  DOI：https://doi.org/10.1007/s10909-020-02373-x
  DOI ID：10.1007/s10909-020-02373-x, ISSN：0022-2291, eISSN：1573-7357
• On-site performance of GroundBIRD, a CMB polarization telescope for large angular scale observations　　　　　　　　　　　　　　　
  Shunsuke Honda; Jihoon Choi; Ricardo Tanausu Génova-Santos; Makoto Hattori; Masashi Hazumi; Takuji Ikemitsu; Hidesato Ishida; Hikaru Ishitsuka; Yonggil Jo; Kenichi Karatsu; Kenji Kiuchi; Junta Komine; Ryo Koyano; Hiroki Kutsuma; Kyungmin Lee; Satoru Mima; Makoto Minowa; Joonhyeok Moon; Makoto Nagai; Takeo Nagasaki; Masato Naruse; Shugo Oguri; Chiko Otani; Michael Peel; Rafael Rebolo-López; José Alberto Rubiño-Martín; Yutaro Sekimoto; Yoshinori Sueno; Junya Suzuki; Tohru Taino; Osamu Tajima; Nozomu Tomita; Yuta Tsuji; Tomohisa Uchida; Eunil Won; Mitsuhiro Yoshida
  Proceedings of SPIE - The International Society for Optical Engineering, Volume：11445, 2020
  © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only. GroundBIRD is a millimeter-wave telescope to observe the polarization patterns of the cosmic microwave background (CMB). The target science topics are primordial gravitational waves from cosmic inflation and reionization optical depth. Therefore, this telescope is designed to achieve the highest sensitivity at large angular scales, ℓ = 6 - 300. For wide sky observations (∼40% full-sky), scanning at a high rotation speed (120°/s) is important to remove atmospheric fluctuations. Microwave kinetic inductance detector (MKID) is utilized with the fast GroundBIRD rotation since its good time response. We have started the commissioning run at the Teide Observatory in the Canary Islands. We report the performance of the telescope, receiver, and data acquisition system, including cooling achievements, observations of astronomical objects, and observations taken during several days ahead of our main survey observations.
  International conference proceedings
  DOI：https://doi.org/10.1117/12.2560918
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85099787475&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85099787475&origin=inward
  DOI ID：10.1117/12.2560918, ISSN：0277-786X, eISSN：1996-756X, SCOPUS ID：85099787475
• High-Resolution Digital SQUID Magnetometer using Sub-Flux Quantum Feedback　　　　　　　　　　　　　　　
  Hiroaki Myoren; Kosuke Okabe; Ryo Matsunawa; Kohki Itagaki; Masato Naruse; Tohru Taino
  14TH EUROPEAN CONFERENCE ON APPLIED SUPERCONDUCTIVITY (EUCAS2019), Volume：1559, 2020
  Digital SQUIDs with the single flux quantum (SFQ) feedback have attracted much attention because of the feasibility of realizing a wide dynamic range and high slew rate for digital magnetometers. In order to realize higher resolution, we have studied a digital SQUID with sub-flux quantum feedback. Combining the sub-flux quantum feedback to a feedback loop and the direct SFQ feedback to a main loop triggered by carry SFQ pulses from an up/down counter. In this study, we discuss the method of multi-flux quantum generation and compact design of the SFQ up/down counter for high-speed operation of the digital SQUID magnetometer.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/1559/1/012013
  DOI ID：10.1088/1742-6596/1559/1/012013, ISSN：1742-6588, eISSN：1742-6596, Web of Science ID：WOS:000558737600013
• A measurement method for responsivity of microwave kinetic inductance detector by changing power of readout microwaves　　　　　　　　　　　　　　　
  H. Kutsuma; M. Hattori; R. Koyano; S. Mima; S. Oguri; C. Otani; T. Taino; O. Tajima
  Applied Physics Letters, Volume：115, Number：3, First page：032603, Last page：032603, Jul. 2019, [Reviewed]
  Superconducting detectors are a modern technology applied in various fields.
  The microwave kinetic inductance detector (MKID) is one of cutting-edge
  superconducting detector. It is based on the principle of a superconducting
  resonator circuit. A radiation entering the MKID breaks the Cooper pairs in the
  superconducting resonator, and the intensity of the radiation is detected as a
  variation of the resonant condition. Therefore, calibration of the detector
  responsivity, i.e., the variation of the resonant phase with respect to the
  number of Cooper-pair breaks (quasiparticles), is important. We propose a
  method for responsivity calibration. Microwaves used for the detector readout
  locally raise the temperature in each resonator, which increases the number of
  quasiparticles. Since the magnitude of the temperature rise depends on the
  power of readout microwaves, the number of quasiparticles also depends on the
  power of microwaves. By changing the power of the readout microwaves, we
  simultaneously measure the phase difference and lifetime of quasiparticles. We
  calculate the number of quasiparticles from the measured lifetime and by using
  a theoretical formula. This measurement yields a relation between the phase
  response as a function of the number of quasiparticles. We demonstrate this
  responsivity calibration using the MKID maintained at 285mK. We also confirm
  consistency between the results obtained using this method and conventional
  calibration methods in terms of the accuracy.
  {AIP} Publishing, Scientific journal
  DOI：https://doi.org/10.1063/1.5110692
  DOI ID：10.1063/1.5110692, ORCID：61935430, arXiv ID：arXiv:1907.03403
• High Sensitivity Photon Sensors Relying on Superconducting Micro Resonators
  Masato NARUSE; Tomohiko ANDO; Ritsuki KUBOTA; Masahiro KUWATA; Tohru TAINO; Hiroaki MYOREN
  TEION KOGAKU (Journal of Cryogenics and Superconductivity Society of Japan), Volume：54, Number：3, First page：174, Last page：180, May 2019
  Cryogenic Association of Japan, Scientific journal
  DOI：https://doi.org/10.2221/jcsj.54.174
  DOI ID：10.2221/jcsj.54.174, ISSN：0389-2441, eISSN：1880-0408
• Readout Circuit Based on Single-Flux-Quantum Logic Circuit for Photon-Number-Resolving SNSPD Array　　　　　　　　　　　　　　　
  Hiroaki Myoren; Satoshi Denda; Kazuki Ota; Masato Naruse; Tohru Taino; Lin Kang; Jian Chen; Peiheng Wu
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：28, Number：4, Jun. 2018
  A read-out circuit for photon-number-resolving superconducting nanowire single-photon detector (SNSPD) based on the single-flux-quantum (SFQ) circuit was designed and the basic performance of the fabricated circuit was confirmed. The current pulse output from an SNSPD array was converted to a SFQ pulse. The SFQ pulse triggered two stacks of double-flux-quantum (DFQ) amplifiers. A single block of a 40-series DFQ amplifier (DFQA) generated 2.3-mV voltage with a rising time of 400 ps for an operation frequency of 1.25 GHz, and the two stacks of DFQA generated 4.6-mV voltage when the SFQ pulse trains supplied both the DFQAs. The total voltage generated by twelve-series of 40-series DFQAs was expected to be 27.6 mV, with the same rising time of 400 ps. Using the fabricated circuit, the 40-series DFQA and the two stacks of the 40-series DFQA generated 2.3- and 4.6-mV voltage, respectively. The output voltage of the SFQ readout circuit was compatible to a room-temperature photon counter with a wide-band low-noise amplifier operating at low temperature.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2018.2809483
  DOI ID：10.1109/TASC.2018.2809483, ISSN：1051-8223, eISSN：1558-2515, Web of Science ID：WOS:000431524600001
• Absorber-coupled lumped element kinetic inductance detectors for gamma-rays　　　　　　　　　　　　　　　
  Masato Naruse; Noriaki Miyamoto; Tohru Taino; Hiroaki Myoren
  PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, Volume：541, First page：36, Last page：39, Oct. 2017, [Reviewed]
  We propose gamma-ray detectors based on superconducting resonators that can be largely multiplexed and show potential for quick response time, high spatial resolution, and high energy resolution. The resonators were fabricated with a niobium film on a silicon wafer. Eight out of ten detectors could be operated at 0.3 K. The detectors were coupled to a 2-mm-thick lead absorber and examined with a cesium 137 source. The pulse decay time was 3.6 mu s and energy resolution was 3.8 keV at 662 keV. We also describe the resonant properties of each detector. The proposed detectors are suitable for use as food-screening systems. (C) 2017 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.physc.2017.08.001
  DOI ID：10.1016/j.physc.2017.08.001, ISSN：0921-4534, eISSN：1873-2143, Web of Science ID：WOS:000410647600006
• Development of STJ for neutron detector on Si-LBO hybrid substrate by surface-activated room-temperature bonding
  S. Endo; G. Fujii; M. Ukibe; H. Takagi; M. Ohkubo; M. Naruse; H. Myoren; C. Otani; T. Taino
  Journal of Physics: Conference Series, Volume：871, Number：1, Jul. 2017, [Reviewed]
  We have been developing superconducting tunnel junctions (STJs) for neutron detector on a Si-Li2B4O7 (LBO) hybrid substrate. An active area of each STJ was limited by dicing in order to obtain high spatial resolution. The Si-LBO hybrid substrate was bonded by a surface-activated room-temperature bonding. In this bonding method, the Si and LBO surfaces were sputter-etched by high energy Ar ion beam and bonded in a vacuum. We fabricated STJs on the Si-LBO hybrid substrate and measured their current-voltage characteristic. Their leakage currents (Ileak) were <
  10 nA, and so we succeeded in fabricating STJs on the Si-LBO hybrid substrate, which can be expected to operate as neutron detectors with high performance.
  Institute of Physics Publishing, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/871/1/012070
  DOI ID：10.1088/1742-6596/871/1/012070, ISSN：1742-6596, ORCID：44982367, SCOPUS ID：85027976830
• Improving the spatial resolution of superconducting tunnel junction THz wave detectors using a modified LiNbO3 absorber　　　　　　　　　　　　　　　
  M. Sone; N. Igarashi; M. Naruse; H. Myoren; Y. Sasaki; C. Otani; T. Taino
  Journal of Physics: Conference Series, Volume：871, Number：1, Jul. 2017, [Reviewed]
  We proposed a superconducting tunnel junction (STJ) detector for terahertz (THz) waves with a modified substrate absorber. The absorber of each STJ was isolated by trenches in order to restrict the diffusion of phonons generated by THz waves, which are made with a dicing process. We evaluated the diffusion characteristics of phonons in the LiNbO3 substrate by detecting THz photons. We found that the phonon diffusion length in a 500-μm-thick LiNbO3 substrate was over 1 mm. No degradation of the current - voltage (I-V) characteristics of the STJ after performing the dicing process.
  Institute of Physics Publishing, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/871/1/012069
  DOI ID：10.1088/1742-6596/871/1/012069, ISSN：1742-6596, SCOPUS ID：85028005068
• Noise Properties of Digital SQUID Using Double Relaxation Oscillation SQUID Comparator With Relaxation Oscillation Resonant Circuit　　　　　　　　　　　　　　　
  Hiroaki Myoren; Ryota Kobayashi; Kenji Kumagai; Masato Naruse; Tohru Taino
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：27, Number：4, Jun. 2017, [Reviewed]
  We designed a digital superconducting quantum interference device (SQUID) system that contains a double relaxation oscillation SQUID (DROS) as a magnetic flux comparator that is connected to an additional relaxation oscillation (RO) circuit with mutually coupled inductances. In the designed digital SQUID, the RO circuit works as a resonator and increases the relaxation oscillation frequency without decreasing the input current of dc/SFQ converters. Numerical simulation shows that the digital SQUID system can operate up to 7 GHz. A fabricated digital SQUID using a DROS comparator with an RO circuit provides correct digital SQUID operation. For a magnetometer using the digital SQUID system, we can realize a magnetic field noise less than 1 pT/root Hz with a small signal bandwidth of more than 10 MHz.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2017.2677422
  DOI ID：10.1109/TASC.2017.2677422, ISSN：1051-8223, eISSN：1558-2515, Web of Science ID：WOS:000399937400001
• CMB polarization experiment "groundBIRD"　　　　　　　　　　　　　　　
  C. Otani; O. Tajima; S. Oguri; S. Mima; J. Choi; T. Damayanthi; N. Furukawa; M. Hattori; M. Hazumi; H. Ishitsuka; R. Koyano; M. Minowa; M. Nagai; T. Nagasaki; Y. Sekimoto; M. Semoto; T. Taino; N. Tomita; T. Uchida; E. Won; M. Yoshida
  27th International Symposium on Space Terahertz Technology, ISSTT 2016, 2017, [Reviewed]
  International conference proceedings
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85021426032&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85021426032&origin=inward
  SCOPUS ID：85021426032
• Fabrication of superconducting tunnel junctions with embedded coil for applying magnetic field　　　　　　　　　　　　　　　
  Kenji Yamaguchi; Hiroshi Nakagawa; Masahiro Aoyagi; Masato Naruse; Hiroaki Myoren; Tohru Taino
  PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, Volume：530, First page：90, Last page：92, Nov. 2016, [Reviewed]
  We have proposed and demonstrated a superconducting tunnel junction (STJ) with an embedded coil for applying a magnetic field. The STJ was fabricated on the coil, which was embedded in a Si substrate. The coil in the Si substrate consists of superconducting microstrip lines and applies a magnetic field to the STJ to suppress the dc Josephson current. The embedded coil was designed with a line and space of 3 mu m and a thickness of 120 nm. To planarize the coil, we employed chemical mechanical polishing (CMP) in our fabrication process. In this STJ, the maximum current of the embedded coil was 28 mA, which corresponded to the maximum magnetic field of 11.76 mT. (C) 2016 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.physc.2016.03.010
  DOI ID：10.1016/j.physc.2016.03.010, ISSN：0921-4534, eISSN：1873-2143, Web of Science ID：WOS:000389518400027
• Fabrication of TiN/AlN/TiN tunnel junctions　　　　　　　　　　　　　　　
  Takeru Nakayama; Masato Naruse; Hiroaki Myoren; Tohru Taino
  PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, Volume：530, First page：87, Last page：89, Nov. 2016, [Reviewed]
  We have fabricated TiN/AlN/TiN tunnel junctions with an epitaxial layer. The critical temperature of TiN can be changed in the range from 0.5 to 5.0 K. Therefore, it is easy to set 5.0 K as the target critical temperature. When a Superconducting Tunnel Junction (STJ) is operated as a photon detector, it is necessary to cool it to within 0.1 K of the critical temperature in consideration of the noise of the thermally stimulated currents. Because 0.3 K was desirable, as for the manufacture of general purpose photon detectors, the critical temperature 5.0 K. TiN and AlN films were deposited by dc and rf magnetron sputtering in a load-lock sputtering system at ambient substrate temperatures. The junctions have a gap voltage of V-g = 1.1 mV, and critical current density of J(c) = 0.24 A/cm(2), and R-sg/R-n of 7.2, and low subgap leakage current (I-sub@ 500 mu V = 180 nA). We report our experiment system, the manufacture method and the junction properties in this paper. (C) 2016 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.physc.2016.04.005
  DOI ID：10.1016/j.physc.2016.04.005, ISSN：0921-4534, eISSN：1873-2143, Web of Science ID：WOS:000389518400026
• Design and Magnetic Field Noise of Magnetometer Using Digital SQUID With Subflux Quantum Feedback　　　　　　　　　　　　　　　
  Hiroaki Myoren; Kouhei Takatoku; Masato Naruse; Tohru Taino
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：26, Number：5, Aug. 2016, [Reviewed]
  Digital superconducting quantum interference devices (SQUIDs) based on single-flux quantum (SFQ) logic have attractive characteristics such as wide dynamic ranges and high slew rates. However, the resolution of a typical digital SQUID is limited by SFQ feedback. To realize lower magnetic field noise by magnetometers using digital SQUIDs, we have adopted two feedback combinations: one, utilizing the SFQ input/output for a main loop and the other, using a mutually coupled loop. The main loop receives direct Phi(0) feedback and subflux quantum feedback Phi(0)/n, where n is an integer from the mutually coupled loop. The flux resolution for the digital SQUID shows improvement with increasing n and reaches below 40 m Phi(0) at n = 2(10); however, the slew rate decreases with increasing n and reaches 1.22 x 10(6)Phi(0)/s at f(c) = 1.25 GHz and n = 2(10). For amagnetometer using a digital SQUID with a pickup loop, we confirmed a magnetic field noise of less than 100 fT/root Hz with a signal bandwidth of 1 MHz for operation frequency f(c) of 20 GHz.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2016.2569500
  DOI ID：10.1109/TASC.2016.2569500, ISSN：1051-8223, eISSN：1558-2515, Web of Science ID：WOS:000380321300001
• Superconductor/Ferromagnet Nanowires for Optical Photon Detection　　　　　　　　　　　　　　　
  R. Cristiano; L. Parlato; U. Nasti; M. Ejrnaes; H. Myoren; T. Taino; R. Sobolewski; G. P. Pepe
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：26, Number：3, Apr. 2016, [Reviewed]
  During the last decade, research on nanowires as superconducting single-photon detectors (SNSPDs or SSPDs) has gained interest due to many experiments demonstrating their fascinating potentialities in several fields. The search for more appealing materials for SNSPDs is presently a hot topic. Several superconductors have been proposed as possible alternatives to NbN, which is presently the racehorse. Examples are WSi and MoSi, which have advantages such as amorphous morphology and narrow-gap and low quasi-particle diffusivity, which permits extending the application in the mid- and far-IR ranges. A strategy based on material hybridization of superconductors with ferromagnets can open a new direction in the development of SNSPD. We present results concerning the hybrid superconducting/ferromagnetic (S/F) single nanowires for SNSPDs. Experiments under laser illumination show a single-photon response of S/Fbased nanowires. The ferromagnetic overlayer has the beneficial effect of an increase of the superconducting critical current density and a decrease of dark counts. We compare dark counts in hybrid S/F with pure S nanowires. The experimental results are explained in terms of the existing models based on the presence of magnetic vortices.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2016.2521579
  DOI ID：10.1109/TASC.2016.2521579, ISSN：1051-8223, eISSN：1558-2515, Web of Science ID：WOS:000372782800001
• Dual-Double Slot Antennas Fabricated with Single Superconducting Film for Millimeter Wave Camera　　　　　　　　　　　　　　　
  Masato Naruse; Tom Nitta; Kenichi Karatsu; Msakazu Sekine; Shigeyuki Sekiguchi; Yutaro Sekimoto; Takashi Noguchi; Tohru Taino; Hiroaki Myoren
  JOURNAL OF INFRARED MILLIMETER AND TERAHERTZ WAVES, Volume：37, Number：2, First page：128, Last page：136, Feb. 2016, [Reviewed]
  We propose an entirely plane-structure camera for millimeter wave astronomy, in order to reduce production cost and time. The camera is composed of a silicon lens-let, antennas, feed lines, and detectors made from the same superconducting aluminum film on a silicon substrate. A couple of double-slot antennas are located the same focal plane of a small substrate lens to enhance the packing density of detectors and observation efficiency. To achieve high sensitivity, we adapted a microwave kinetic inductance detector as a photon sensor, which consists of a superconducting microresonator. We examined the optical performance of the camera attached to a silicon lens array at 220 GHz in a 0.3 K cryostat. The measured beams were in good agreement with the calculations within the dynamic range of the setup (20 dB). Polarization misalignments between the dual-double slot antenna were less than 2(a similar to), and cross-polarization level was around -7 dB. The relatively high cross-polarization would be explained by an antenna crosstalk mediated by quasiparticle diffusion.
  SPRINGER, English, Scientific journal
  DOI：https://doi.org/10.1007/s10762-015-0216-y
  DOI ID：10.1007/s10762-015-0216-y, ISSN：1866-6892, eISSN：1866-6906, Web of Science ID：WOS:000368053700002
• Terahertz response of NbN-based microwave kinetic inductance detectors with rewound spiral resonator
  S. Ariyoshi; K. Nakajima; A. Saito; T. Taino; C. Otani; H. Yamada; S. Ohshima; J. Bae; S. Tanaka
  Superconductor Science and Technology, Volume：29, Feb. 2016, [Reviewed]
  © 2016 IOP Publishing Ltd. We have developed microwave kinetic inductance detectors (MKIDs) consisting of dual-purpose rewound spirals (spiral-MKIDs) made of a metal nitride superconductor for terahertz imaging applications. An NbN-based spiral-MKID array with 25 pixels was fabricated, and the fundamental performance of the terahertz receptivity was evaluated at the equilibrium temperature of a conventional 4 He refrigerator (≃3 K). The microwave transmission property of the array showed the 25 resonance lines, equally separated by frequency, in the microwave range from 2.70 to 2.95 GHz. To evaluate its optical performance as a terahertz detector, we measured the spiral-MKID's spectral response, response time, and noise equivalent power (NEP), and confirmed that it revealed a broad spectral response from 1 to 9 THz and an effective response time of approximately 80 μs. The noise-equivalent power was estimated to be .
  English
  DOI：https://doi.org/10.1088/0953-2048/29/3/035012
  DOI ID：10.1088/0953-2048/29/3/035012, ISSN：0953-2048, SCOPUS ID：84960158097
• Thermal fluctuations in superconductor/ferromagnet nanostripes　　　　　　　　　　　　　　　
  U. Nasti; L. Parlato; M. Ejrnaes; R. Cristiano; T. Taino; H. Myoren; Roman Sobolewski; G. Pepe
  PHYSICAL REVIEW B, Volume：92, Number：1, Jul. 2015, [Reviewed]
  Thermal fluctuations in hybrid superconductor/ferromagnetic NbN/NiCu bilayers, as well as in pure superconducting NbN, two-dimensional (2D), nanostripes, have been investigated in order to understand the origin of dark counts in superconducting nanostripes when operated as single-photon detectors in the temperature range from 4.2 to 8 K. In 2D superconductors, the dynamics of vortex motion play a significant role in the formation of a transient normal state, leading to dark-count events in current-biased nanostripes. By introducing a weak ferromagnetic overlayer on top of pure NbN, we managed to control the vortex dynamics, which subsequently enabled us to differentiate between several proposed theoretical models. In particular, a 6 - nm - thick NiCu film grown on top of 8 - nm - thick NbN nanostripes led to an enhanced critical current density in the resulting nanostructure, as well as significantly lowered fluctuation rates, as compared to pure NbN structures, leading to reduced dark counts. The enhancement of pinning in NbN/NiCu bilayers provided evidence that thermal excitations of single vortices (vortex hopping) near the edge of a 2D nanostripe were the dominant mechanism of the observed dark-count transients. On the other hand, in pure NbN the leading source of thermal fluctuations was the current-assisted thermal unbinding of vortex-antivortex pairs.
  AMER PHYSICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1103/PhysRevB.92.014501
  DOI ID：10.1103/PhysRevB.92.014501, ISSN：1098-0121, eISSN：1550-235X, Web of Science ID：WOS:000357484100007
• Single-Flux Quantum Readout Circuits for Photon-Number-Resolving Superconducting Nanowire Single-Photon Detectors　　　　　　　　　　　　　　　
  Hiroaki Myoren; Shunsuke Takeda; Masato Naruse; Tohru Taino; Jian Chen; Peiheng Wu
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：25, Number：3, Jun. 2015, [Reviewed]
  Superconducting nanowire single-photon detectors (SNSPDs) with series-parallel meander-type configurations are demonstrated to have photon-number-resolving capabilities and are expected to be used for an evaluation system of single-photon generators and/or an energy-resolved fast detector for a new-generation time-of-flight mass spectrometry. In this paper, we present the design, fabrication, and confirmation of correct operations of two kinds of single-flux-quantum (SFQ) digital readout circuits for an SNSPD with a series-parallel meander-type configuration. Assuming a six-parallel meander-type configuration, we designed: 1) a six-level current discriminator using six different magnetically coupled DC/SFQ converter circuits; and 2) a Delta-type A/D converter using a quasi-one-junction SQUID (QOS) comparator with an SFQ feedback loop. For the design of the magnetically coupled inputs, we used a 3-D inductance extraction program FastHenry and the designed circuits were fabricated using a HYPRES 4.5-kA/cm(2) Nb process and a National Institute of Advanced Industrial Science and Technology (AIST) standard 2.5-kA/cm(2) Nb process.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2014.2365356
  DOI ID：10.1109/TASC.2014.2365356, ISSN：1051-8223, eISSN：1558-2515, Web of Science ID：WOS:000384888700001
• Relationship Between Loaded Quality Factor and Responsivity for NbN-Based MKIDs Using Dual-Function Spiral Strip　　　　　　　　　　　　　　　
  A. Saito; K. Nakajima; K. Hayashi; Y. Ogawa; Y. Okuyama; D. Oka; S. Ariyoshi; H. Yamada; T. Taino; C. Otani; J. Bae; S. Ohshima
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：25, Number：3, Jun. 2015, [Reviewed]
  We investigated the relationship between loaded quality factor (QL) and responsivity of microwave kinetic inductance detectors (MKIDs) using a dual-function spiral strip (DFSS). Three types of DFSSs with different QL values were designed, and the S-21 properties were simulated when kinetic inductance of a superconductor was changed by using a 2.5-dimentional simulator. The simulated results showed that a very high Q(L) value was not necessarily required. The resonator frequencies of the 25-MKID array using a better type of DFSS (Q(L) similar to 3500) were adjusted to be separated by 5MHz around 2.0 GHz. The 25-MKID array were fabricated using 20-nm thick niobium nitride films deposited on r-plane sapphire substrates. We clearly observed 25 half-wavelength resonances around 2.0 GHz at 2.245 K. The optical responses were also confirmed using hot and cold radiation. The dependence of the responsivity on the Q(L) indicated that the Q(L) value of approximately 2000 could obtain higher responsivity.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2014.2367459
  DOI ID：10.1109/TASC.2014.2367459, ISSN：1051-8223, eISSN：1558-2515, SCOPUS ID：84925067950, Web of Science ID：WOS:000351465400011
• Design and Performance of Digital SQUID with Sub-Flux Quantum Resolution　　　　　　　　　　　　　　　
  Hiroaki Myoren; Kouhei Takatoku; Masato Naruse; Tohru Taino
  2015 15TH INTERNATIONAL SUPERCONDUCTIVE ELECTRONICS CONFERENCE (ISEC), 2015, [Reviewed]
  Digital SQUIDs based on the single flux quantum (SFQ) logic have attractive characteristics, such as wide dynamic range and high slew rate. However, the resolution of digital SQUIDs is limited to SFQ. To realize sub-flux quantum resolution for these SQUIDs, we have adopted two types of feedback combinations: one with the SFQ input/output for a main loop and the other with a mutually coupled loop. The main loop receives direct Phi(0) feedback and sub-flux quantum feedback Phi(0)/n, where n is an integer, from the mutually coupled loop. We confirmed the correct operation of our device at a clock frequency of 1.25 GHz for a digital SQUID with a sub-Phi(0) flux feedback resolution of Phi(0)/8 from circuit simulation. The slew rate is found to be 1.56x10(8) Phi(0)/s in this simulation (f(c) = 1.25 GHz, n=8). The flux resolution for the digital SQUID shows improvement with increasing n and reached below 40 m Phi(0) with n=2(10); however the slew rate is decreased with increasing n and reached 1.22x10(6) Phi(0)/s with f(c)=1.25 GHz and n=2(10).
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000380391200018
• SFQ Amplified Circuit for Photon-Number-Resolving SNSPD Array　　　　　　　　　　　　　　　
  Kazuki Ota; Masato Naruse; Tohru Taino; Hiroaki Myoren; Jian Chen; Lin Kang; Peiheng Wu
  2015 15TH INTERNATIONAL SUPERCONDUCTIVE ELECTRONICS CONFERENCE (ISEC), 2015, [Reviewed]
  Superconducting nanowire single-photon detectors (SNSPDs) with series-parallel meander-type configuration are demonstrated to have photon-number-resolving (PNR) capabilities. Based on this unique feature, SNSPDs are expected to be used in the evaluation of single photon sources. However, increasing the number of SNSPDs causes an increase in the heat flow and further degradation in the timing jitter. To resolve this problem, the use of single flux quantum (SFQ) logic circuits is proposed. In this study, we present the read-out circuit for the SNSPD array, based on the SFQ logic. Our design of the read-out circuit makes it feasible to simultaneously process six SNSPD signals at 500 MHz and amplify the output voltage as an input to other circuits without the need for any amplifiers. We confirm using simulations that our designed read-out circuit has these capabilities. Furthermore, it is shown that the output voltage increases by 4.8 mV, proportional to the number of SNSPD signals and the output voltage is between 4.8 and 27.8 mV.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000380391200053
• Design and Fabrication of Microwave Kinetic Inductance Detectors using NbN Symmetric Spiral Resonator Array　　　　　　　　　　　　　　　
  K. Hayashi; A. Saito; Y. Ogawa; M. Murata; T. Sawada; K. Nakajima; H. Yamada; S. Ariyoshi; T. Taino; H. Tanoue; C. Otani; S. Ohshima
  11TH EUROPEAN CONFERENCE ON APPLIED SUPERCONDUCTIVITY (EUCAS2013), PTS 1-4, Volume：507, 2014, [Reviewed]
  We designed and fabricated a microwave kinetic inductance detector (MKID) using a niobium nitride (NbN) symmetric spiral resonator array. Previously we revealed that a rewound spiral structure works as not only a high-Q half-wavelength resonator but also as a broadband terahertz antenna. We conducted simulations for a 9 resonator array assuming NbN as the superconducting material and sapphire as the dielectric substrate, and obtained a maximum attenuation of over 30 dB and unloaded quality factors of over 2x10(5) for frequencies between 4.4 and 4.9 GHz. We fabricated the 9 resonator array MKID using NbN thin film deposited on an m-sapphire substrate by using dc magnetron sputtering. We observed half-wavelength resonances of around 4.5 GHz at 4 K. We measured the optical response of the MKID. The frequency shift was 0.5 MHz when illuminated with 650 nm photons.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/507/4/042015
  DOI ID：10.1088/1742-6596/507/4/042015, ISSN：1742-6588, SCOPUS ID：84902254537, Web of Science ID：WOS:000350818300183
• NbN-Based Microwave Kinetic Inductance Detector with a Rewound Spiral Resonator for Broadband Terahertz Detection　　　　　　　　　　　　　　　
  S. Ariyoshi; K. Nakajima; A. Saito; T. Taino; H. Tanoue; K. Koga; N. Furukawa; H. Yamada; S. Ohshima; C. Otani; J. Bae
  Applied Physics Express, Volume：6, Number：6, First page：1, Last page：64103, Jun. 2013, [Reviewed]
  We propose a microwave kinetic inductance detector consisting of an NbN rewound spiral resonator (spiral-MKID) as a possible broadband terahertz detector operating with a conventional cryogen-free 4 He refrigerator. The spiral-MKIDs fabricated with NbN films reveal high-Q microwave resonation with loaded Q factors on the order of 10 4 at 3 K, and the temperature dependence of the microwave resonance frequency is well fitted by the Mattis-Bardeen theory. The optical response was confirmed in the terahertz range below 2.4 THz. We also discuss the expected noise equivalent power of the NbN-based MKIDs. © 2013 The Japan Society of Applied Physics.
  DOI：https://doi.org/10.7567/APEX.6.064103
  DOI ID：10.7567/APEX.6.064103, ISSN：1882-0778, J-Global ID：201302256982153041, SCOPUS ID：84880863334, Web of Science ID：WOS:000320167300033
• Optical Efficiencies of Lens-Antenna Coupled Kinetic Inductance Detectors at 220 GHz　　　　　　　　　　　　　　　
  Masato Naruse; Yutaro Sekimoto; Takashi Noguchi; Akihira Miyachi; Kenichi Karatsu; Tom Nitta; Masakazu Sekine; Yoshinori Uzawa; Tohru Taino; Hiroaki Myoren
  IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY, Volume：3, Number：2, First page：180, Last page：186, Mar. 2013
  We have been developing a terahertz camera based on antenna-coupled superconducting resonators, the so-called microwave kinetic inductance detectors (MKIDs), and a silicon lens array. The MKID consists of a coplanar waveguide coupled to a double slot antenna and is patterned on a high-quality aluminum film grown by molecular beam epitaxy. The camera is sensitive at frequencies of 200-240 GHz. Its bandwidth is limited by the impedance properties of the double slot antenna. The design, fabrication, and optical evaluations of the planar antennas and silicon lens arrays are presented in this paper. The MKID camera has been evaluated both in dark conditions and under optical radiation in a 0.1-K dilution refrigerator. The electrical noise equivalent power was around 5x10(-18)W/root HZ in dark conditions and 4x10(-16)W/root HZ, which is much lower than the photon noise level, with the optical load. The optical efficiency of the camera was estimated by three independent methods, and the results were consistent with each other and equal to 20%-25% without an anti-reflection coating on the lens surface.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TTHZ.2012.2237029
  DOI ID：10.1109/TTHZ.2012.2237029, ISSN：2156-342X, eISSN：2156-3446, Web of Science ID：WOS:000318770300010
• Performance of superconducting single-photon detectors using NbN/NiCu nanowires　　　　　　　　　　　　　　　
  H. Myoren; S. Taguchi; K. Ohshima; T. Wakatsuki; T. Taino; L. Parlato; G. P. Pepe
  IEEE Transactions on Applied Superconductivity, Volume：23, Number：3, 2013, [Reviewed]
  We present optical properties of nanowires consisting of both proximitized superconductor/ferromagnet bilayers of NbN/NiCu and pure superconducting NbN layers. Thin NbN/NiCu hetero-structures were deposited on MgO(100) substrates by in situ dc magnetron sputtering, while nanowires were patterned using standard electron beam lithography and reactive ion etching. Photo-response signals were recorded from 100-nm-wide, three-parallel and six-series NbN(8 nm)/NiCu nanowires by 850-nm pulsed laser irradiation (time width 400 ps, repetition rate ∼100 MHz). For the latter configuration the fall time of voltage responses was found to be close to 1.7 ns, and it gradually increased with increasing the NiCu film thickness. Moreover, three discrete families of photo-response signals recorded for the three-parallel and six-series nanowires were also observed. © 2002-2011 IEEE.
  English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2013.2252344
  DOI ID：10.1109/TASC.2013.2252344, ISSN：1051-8223, SCOPUS ID：84876135686
• Microwave property and optical response of MKIDs using NbN symmetrical spiral resonator array　　　　　　　　　　　　　　　
  A. Saito; K. Hayashi; K. Nakajima; S. Ariyoshi; Y. Ogawa; H. Yamada; T. Taino; H. Tanoue; C. Otani; J. Bae; S. Ohshima
  2013 38TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ), 2013, [Reviewed]
  We investigated the microwave properties and optical responses of the microwave kinetic inductance detectors (MKIDs) using niobium nitride (NbN) symmetric spiral resonator array for Fourier transform terahertz spectrometer. The 9-arrays MKIDs were designed around 4.7 GHz and fabricated using the NbN thin film deposited on the m-sapphire substrate. The microwave responses of the 9-arrays MKIDs were measured using a low-noise amplifier and a vector network analyzer. We observed nine half-wavelength resonances around 4.7 GHz at 4.2 K. The frequency shifts of the resonances were also observed by an optical irradiation.
  IEEE, English, International conference proceedings
  ISSN：2162-2027, Web of Science ID：WOS:000345855300391
• SFQ Digital Signal Processing Circuits for Multi-Quantum Beam Detectors using STJ Array with Neutron Absorbers　　　　　　　　　　　　　　　
  Hiroaki Myoren; Yuta Akamatsu; Ryo Sasaki; Shoji Sato; Masato Naruse; Tohru Taino
  2013 IEEE 14TH INTERNATIONAL SUPERCONDUCTIVE ELECTRONICS CONFERENCE (ISEC), 2013, [Reviewed]
  We studied multi-quantum beam detectors using a superconducting tunnel junction (STJ) array with neutron absorbers. Using a neutron absorber for each of the STJs, we expected the STJ detector to exhibit a high spatial resolution and high detection efficiency for neutrons as well as radiative beams such as X-rays. To obtain diffraction patterns of the Xray and neutrons, we propose the use of a multi-quantum beam detector using an STJ array and single flux quantum (SFQ) signal processing at low temperature because of its high-speed and low-power operation. The kinetic energy is determined for individual neutrons using time-of-flight-methods that employ SFQ time-to-digital converters (TDCs). To separately detect alpha-particles and gamma-ray particles that are produced by the nuclear reaction between neutrons and boron, and X-ray photons, excess quasi-particle currents of the STJ detectors are processed by V/F type analog-to-digital converters and T-FF binary counters using SFQ digital circuits. To obtain the multiplexed readout of an STJ detector array, we designed a current bias switching circuit controlled by an SFQ driver for time-domain multiplexing. We designed the main circuits for this SFQ signal processing system and fabricated them using the ISTEC SRL Nb standard process II (STP2).
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000333277300034
• Design of Digital DROS for Wide Dynamic Operation Range with sub-single flux quantum resolution　　　　　　　　　　　　　　　
  Hiroaki Myoren; Kohsuke Terui; Naoya Shimada; Tohru Taino
  SUPERCONDUCTIVITY CENTENNIAL CONFERENCE 2011, Volume：36, First page：121, Last page：126, 2012, [Reviewed]
  We designed a digital double relaxation oscillation SQUID (DROS) with an single flux quantum (SFQ) feedback circuit for digital SQUID magnetometers. The DROS is magneticall coupled to a feedback SQUID loop and a signal magnetic flux is input to the feedback SQUID loop. The DROS generates two kinds of voltage pulses corresponding to the total magnetic flux in the feedback SQUID loop. Those voltage pulses are converted to SFQ and anti-SFQ pulses and input to the feedback SQUID loop to keep the magnetic flux in the feedback SQUID loop constant. A read-out dc SQUID (R/O SQUID) is also magnetically coupled to the feedback SQUID loop for monitoring the actual magnetic flux in the feedback SQUID loop. The number of the generated SFQ pulses is estimated by SFQ feedback steps on output voltage curves generated from the R/O SQUID. Wide dynamic operation range is realized by the SFQ feedback and sub-Phi(0) magnetic flux resolution is realized by the R/O SQUID, where Phi(0)(= h/2e) is the single magnetic flux quantum. Also one digital DROS magnetometer can be operated with less than 10 mA. We fabricated a designed digital DROS using ISTEC SRL 2.5 kA/cm(2) Nb standard process II and are trying to confirm the correct operation of the digital DROS. (C) 2012 Published by Elsevier B.V. Selection and/or peer-review under responsibility of the Guest Editors.
  ELSEVIER SCIENCE BV, English, International conference proceedings
  DOI：https://doi.org/10.1016/j.phpro.2012.06.057
  DOI ID：10.1016/j.phpro.2012.06.057, ISSN：1875-3892, Web of Science ID：WOS:000314403400022
• Design of Digital DROS With SFQ Up/Down Counter for Wide Dynamic Operation Range　　　　　　　　　　　　　　　
  Hiroaki Myoren; Yun Kimimoto; Kosuke Terui; Tohru Taino
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：21, Number：3, First page：387, Last page：390, Jun. 2011, [Reviewed]
  We designed a digital double relaxation oscillation SQUID (DROS) with an SFQ up/down counter. The DROS is connected to a feedback SQUID loop and a signal magnetic flux is input to the feedback SQUID loop. The DROS generates two kinds of voltage pulses corresponding to the total magnetic flux in the feedback SQUID loop. Two kind of voltage pulses are converted to SFQ and anti-SFQ pulses and input to the feedback SQUID loop to keep the magnetic flux in the SQUID loop constant. The number of the generated SFQ pulses is counted using the SFQ up/down counter. Thus, the count corresponds to the input magnetic flux. Because the SFQ up/down counter is operated in the pulse driven mode, the digital DROS needs only dc bias current for operation. We designed and fabricated a digital DROS with a relaxation oscillation frequency of 3 GHz and an 8-bit SFQ up/down counter. Numerical simulation suggested the designed digital DROS has a dynamic range exceeding +/- 100 Phi(0) and magnetic flux slew rate of 3 x 10(9) Phi(0)/s.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2010.2100800
  DOI ID：10.1109/TASC.2010.2100800, ISSN：1051-8223, Web of Science ID：WOS:000291050500068
• Strong critical current density enhancement in NiCu/NbN superconducting nanostripes for optical detection　　　　　　　　　　　　　　　
  N. Marrocco; G. P. Pepe; A. Capretti; L. Parlato; V. Pagliarulo; G. Peluso; A. Barone; R. Cristiano; M. Ejrnaes; A. Casaburi; N. Kashiwazaki; T. Taino; H. Myoren; Roman Sobolewski
  APPLIED PHYSICS LETTERS, Volume：97, Number：9, Aug. 2010, [Reviewed]
  We present measurements of ferromagnet/superconductor (NiCu/NbN) and plain superconducting (NbN) nanostripes with the linewidth ranging from 150 to 300 nm. The NiCu (3 nm)/NbN (8 nm) bilayers, as compared to NbN (8 nm), showed a up to six times increase in their critical current density, reaching at 4.2 K the values of 5.5 MA/cm(2) for a 150 nm wide nanostripe meander and 12.1 MA/cm(2) for a 300 nm one. We also observed six-time sensitivity enhancement when. the 150 nm wide NiCu/NbN nanostripe was used as an optical detector. The strong critical current enhancement is explained by the vortex pinning strength and density increase in NiCu/NbN bilayers and confirmed by approximately tenfold increase in the vortex polarizability factor. (C) 2010 American Institute of Physics. [doi:10.1063/1.3479529]
  AMER INST PHYSICS, English, Scientific journal
  DOI：https://doi.org/10.1063/1.3479529
  DOI ID：10.1063/1.3479529, ISSN：0003-6951, Web of Science ID：WOS:000282187200042
• Photoresponse experiments on NbN proximized nanostructures　　　　　　　　　　　　　　　
  G. P. Pepe; L. Parlato; V. Pagliarulo; N. Marrocco; C. De Lisio; G. Peluso; A. Barone; T. Taino; H. Myoren; A. Casaburi; M. Ejrnaes; R. Cristiano
  9TH EUROPEAN CONFERENCE ON APPLIED SUPERCONDUCTIVITY (EUCAS 09), Volume：234, 2010, [Reviewed]
  Among superconducting materials used in developing high performance nanowire detectors, NbN demonstrated to have unique characteristics in terms of fast response time, quantum efficiency and photon-number resolving capability. We investigated the role of proximity effect on superconducting NbN thin films covered by a weak ferromagnetic NiCu thin layer. Hetero-structures NbN/NiCu have been deposited by DC magnetron sputtering on MgO substrates without any heating. Characterization in terms of morphological, transport, and ultra-fast optical properties has been done. Superconducting nanowires with meander-type geometries (48 micron lengths and <500 nm widths) have been designed and fabricated. Preliminary results concerning their photoresponse to 1550nm laser irradiation are presented.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/234/4/042027
  DOI ID：10.1088/1742-6596/234/4/042027, ISSN：1742-6588, Web of Science ID：WOS:000304593700192
• Terahertz Detector based on a Superconducting Tunnel Junction Coupled to a Thin Superconductor Film　　　　　　　　　　　　　　　
  S. Ariyoshi; T. Taino; A. Dobroiu; H. Sato; H. Matsuo; C. Otani
  Applied Physics Letters, Volume：95, Number：19, First page：193504, Nov. 2009, [Reviewed]
  The principle of a terahertz detector using a superconducting tunnel junction (STJ) coupled to a large terahertz-absorbing superconductor film is verified. We have detected terahertz radiation based on the Cooper-pair breaking process, and confirmed that the sensitivity has a sharp increase around 0.7 THz, a value that is in agreement with the gap frequency of the superconducting Nb. For high-sensitivity terahertz detection, we propose an improved design of the STJ detector composed of a smaller junction coupled to a thinner superconductor film. We also discuss the expected noise equivalent power of the optimized detector. © 2009 American Institute of Physics.
  English
  DOI：https://doi.org/10.1063/1.3263711
  DOI ID：10.1063/1.3263711, ISSN：0003-6951, J-Global ID：200902242140726040, SCOPUS ID：70449715543, Web of Science ID：WOS:000272756600077
• SFQ Multiplexed Signal Processing Circuits for STJ Photon Detector Arrays　　　　　　　　　　　　　　　
  Hiroaki Myoren; Yu Yoshizawa; Tohru Taino
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：19, Number：3, First page：413, Last page：416, Jun. 2009, [Reviewed]
  We have been studying single flux quantum (SFQ) digital signal processing (DSP) circuits for superconducting tunnel junction (STJ) photon detector arrays. The proposed DSP circuit consists of a binary tree of multiplexers, a time counter, a binary counter, and a readout memory. Each multiplexer was designed such that the first arriving SFQ pulse train connects to the binary counter until the time counter reaches a set value. The time counter is set to a sufficiently long time compared with the response time of STJ photon detector. After processing the multiplexer, SFQ pulses are integrated by the binary counter. The number of integrated SFQ pulses is proportional to the number of quasi-particles generated by photon irradiation in an STJ. After the time counter reaches the set value, the time counter generates a set SFQ pulse to set the multiplexer in the ready state, the integrated value is sent to the readout memory and then the binary counter is reset. The binary tree of multiplexers could be extended to have address bits for photon imaging using an STJ array. One key component of the proposed DSP circuit was fabricated and its operation using an on-chip clock generator was successfully demonstrated.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2009.2017947
  DOI ID：10.1109/TASC.2009.2017947, ISSN：1051-8223, Web of Science ID：WOS:000268282000067
• Superconducting NbN Nanowire Photo Switches for Generating Single Flux Quantum Pulses　　　　　　　　　　　　　　　
  Hiroaki Myoren; Yusuke Mada; Yuji Matsui; Tohru Taino; Susumu Takada
  8TH EUROPEAN CONFERENCE ON APPLIED SUPERCONDUCTIVITY (EUCAS'07), Volume：97, 2008, [Reviewed]
  We investigated superconducting NbN nanowire as a photo switch for generating single flux quantum (SFQ) pulses. Epitaxially grown NbN thin films were prepared on MgO(100) substrates by a dc magnetron sputtering method using gas mixture of Ar + N(2), without substrate heating. NbN thin films showed Tc of 13.6 K for 8 nm, and 10 K for 4 nm. NbN nanowires were patterned using a electron beam lithography with 200 nm thick electron beam resist. To increasing photo-sensitive regions, we fabricated 50 x 50 1 m 2 meander patterns with NbN nanowires. Line width of nanowires was varied from 150 nm to 500 nm. Critical current density of NbN nanowires was about 3x10(6) A/cm(2) at 4.2 K. We irradiated 850-nm laser pulses via 50-1 m multi-mode optical fibers. Repetition frequency and pulse width could be controlled by a pulse pattern generator. The maximum laser pulse power was about 1 mW. Using 150-nm-wide NbN nanowires, half of critical current was suppressed by 1 mW CW laser irradiations. High speed responses were observed for laser pulses with repetition frequency of 1 MHz and pulse width of 2 ns. Besides the NbN nanowire photo switches, we designed an SFQ interface circuit based on Josephson transmission lines. The designed circuit could generate SFQ pulses by input current of 10 mu A, 25 GHz current pulses. Dc bias margin of the circuit was +/-15% for 60 mu A current pulses.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/97/1/012329
  DOI ID：10.1088/1742-6596/97/1/012329, ISSN：1742-6588, Web of Science ID：WOS:000276054100328
• X-ray detection using superconducting tunnel junction shaped normal-distribution-function　　　　　　　　　　　　　　　
  Taino Tohru; Nishihara Tomohiro; Hoshino Koichi; Myoren Hiroaki; Sato Hiromi; Shimizu Hirohiko M; Takada Susumu
  IEICE TRANSACTIONS ON ELECTRONICS, Volume：E90C, Number：3, First page：566, Last page：569, Mar. 2007, [Reviewed]
  DOI：https://doi.org/10.1093/ietele/e90-c.3.566
  DOI ID：10.1093/ietele/e90-c.3.566, ISSN：0916-8524, Web of Science ID：WOS:000245194400004
• Supuerconducting Detector Array for Terahertz Imaging Applications　　　　　　　　　　　　　　　
  Seiichiro Ariyoshi
  Japanese Journal of Applied Physics, Volume：45, Number：37-41, First page：1004, Last page：1006, Oct. 2006, [Reviewed]
  We designed, fabricated, and characterized a superconducting detector array for terahertz imaging applications. To evaluate the optical performance as an imaging array, we measured the spectral response of a 5-pixel linear array detector, and confirmed its sensitivity peaks to be at the same frequency within accuracy of one percent in the range of 0.65 THz. The frequency peaks are also in good agreement with a numerical calculation. This linear array was tested in the nondestructive imaging of a metallic pattern and an integrated-circuit card, and allowed the shortening of the total acquisition time. High fabrication yield of about 99% was achieved for single superconducting tunnel junctions, which led to 90% yield for the detectors. ©2006 The Japan Society of Applied Physics.
  DOI：https://doi.org/10.1143/JJAP.45.L1004
  DOI ID：10.1143/JJAP.45.L1004, ISSN：0021-4922, J-Global ID：200902218979489339, SCOPUS ID：34547842743, Web of Science ID：WOS:000241902400005
• Direct and Indirect Detection of Terahertz Waves using a Nb-based Superconducting Tunnel Junction　　　　　　　　　　　　　　　
  Chiko Otani
  Journal of Physics, Volume：43, Number：1, First page：1303, Last page：1306, Jun. 2006, [Reviewed]
  We are developing a broadband THz detectors using Nb-based superconducting tunnel junctions. We found two components in a current signal for 1-2 THz pulse input. From the comparison of results obtained for the signals, the frequency response for the different size of STJs and the STJs fabricated on different substrate materials, we demonstrate that they correspond to photons absorbed with the superconductor electrode (referred as 'direct' component) and phonons generated by photons absorbed with the substrate (referred as 'phononmediated' component). © 2006 IOP Publishing Ltd.
  English
  DOI：https://doi.org/10.1088/1742-6596/43/1/318
  DOI ID：10.1088/1742-6596/43/1/318, ISSN：1742-6588, J-Global ID：201502838637692014, SCOPUS ID：33746301378, Web of Science ID：WOS:000277479400318
• Terahertz imaging with a direct detector based on superconducting tunnel junctions　　　　　　　　　　　　　　　
  S. Ariyoshi; C. Otani; A. Dobroiu; H. Sato; K. Kawase; H. M. Shimizu; T. Taino; H. Matsuo
  Applied Physics Letters, Volume：88, Number：20, May 2006
  We demonstrated terahertz imaging using a direct detector based on niobium superconducting tunnel junctions (STJs). The detector is composed of linearly distributed junctions placed on a superconducting microstrip line and is integrated on two wings of a log-periodic antenna. We succeeded nondestructive imaging for an integrated-circuit card and dry material using the detector around its sensitivity peak (∼0.66 THz). The dynamic range was measured to be higher than 4× 107 (76 dB). Thus, the STJ detector is applicable to high-sensitivity and high-speed terahertz imaging for various nondestructive inspection applications. © 2006 American Institute of Physics.
  Scientific journal
  DOI：https://doi.org/10.1063/1.2204842
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=33646892904&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=33646892904&origin=inward
  DOI ID：10.1063/1.2204842, ISSN：0003-6951, SCOPUS ID：33646892904
• A broadband terahertz detector using a superconducting tunnel junction　　　　　　　　　　　　　　　
  Tohru Taino
  Nuclear Instruments and Methods in Physics Research A, Volume：559, Number：2, First page：751, Last page：753, Apr. 2006, [Reviewed]
  We have proposed and demonstrated a new broadband terahertz (THz) wave detector using a superconducting tunnel junction (STJ) fabricated on LiNbO 3 , LiTaO 3 , and sapphire substrates. These substrates have relatively high absorption efficiency for THz waves, and we have expected that incident THz waves from substrate side are absorbed and that generate many THz phonons which break Cooper pairs in the base superconductor electrode of the STJ. Using a frequency-tunable THz pulse source in 1-2 THz, we have confirmed that the current signal corresponding to the THz input was observed. In addition, we found two current components with different timescales for the first time. We interpret that the slow component corresponds to phonons absorbed with the substrate and that the fast one corresponds to the directly absorbed photons with the superconductor electrode of the STJs. © 2006 Elsevier B.V. All rights reserved.
  English
  DOI：https://doi.org/10.1016/j.nima.2005.12.207
  DOI ID：10.1016/j.nima.2005.12.207, ISSN：0168-9002, J-Global ID：201102205561735299, SCOPUS ID：33645883838
• Polyimide Buffer Layer for STJ Photon Detector　　　　　　　　　　　　　　　
  T. Taino; M. Yoshida; M. Narisawa; H. Myoren; K. Kikuchi; H. Nakagawa; M. Aoyagi; H. Sato; H. M. Shimizu; S. Takada
  7TH EUROPEAN CONFERENCE ON APPLIED SUPERCONDUCTIVITY (EUCAS'05), Volume：43, First page：1319, Last page：1321, 2006, [Reviewed]
  We have proposed and been developing ultra low noise photon detector using superconducting tunnel junctions (STJs). The STJs are fabricated on polyimide ( PI) layer which is prepared on sapphire substrate. The PI is coated on the substrate before making the STJ. It acts as buffer layer to suppress a great deal of phonon events which come from the substrate. For low energy application such as soft X-ray and extreme ultraviolet, the STJs with PI buffer layer is a very attractive detector because the spectrum of low energy photons can measured clearly without noise that depends on phonon events in the substrate. We fabricated the STJs with PI buffer layer which are different thickness and measured X-ray spectrum of 5.9 keV. We found that polyimide of 100 nm thickness is enough to suppress phonon events in low energy range.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/43/1/322
  DOI ID：10.1088/1742-6596/43/1/322, ISSN：1742-6588, Web of Science ID：WOS:000277479400322
• Quasiparticles Injection Effects for Nb/Al/AlOx/Al/Nb Tunnel Junctions at 0.4K using Stacked Josephson Junctions　　　　　　　　　　　　　　　
  Hiroaki Myoren; Akiko Shigihara; Tohru Taino; Susumu Takada
  7TH EUROPEAN CONFERENCE ON APPLIED SUPERCONDUCTIVITY (EUCAS'05), Volume：43, First page：1326, Last page：1329, 2006, [Reviewed]
  We have studied on the quasiparticles (QPs) injection effects for Nb/Al/AlOx/Al/Nb tunnel junctions at 0.4 K. A device structure was a stack of an injector Josephson junction (JJ) and a detector JJ. At a low temperature, there is small number of thermally excited QPs and we expected to observe easily the QPs injection effect of the detector JJ using the injector JJ. In this study, the structure of the Nb/Al/AlOx/Al/Nb tunnel junctions was the same for X-ray detectors using superconducting tunnel junctions. For constant-QPs current injection, we expected a small-signal current gain exceed the unity. We used pulsed-QPs current with changing pulse duration. For long duration, I-V curves for the detection junctions were sum of original current and QP current. On the other hands, for short duration time, the I-V curves showed different shapes from those for the long duration time.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/43/1/324
  DOI ID：10.1088/1742-6596/43/1/324, ISSN：1742-6588, Web of Science ID：WOS:000277479400324
• THz imaging with a linear array detector based on superconducting tunnel junctions　　　　　　　　　　　　　　　
  S. Ariyoshi; C. Otani; A. Dobroiu; H. Matsuo; H. Sato; T. Taino; K. Kawase; H. M. Shimizu
  CONFERENCE DIGEST OF THE 2006 JOINT 31ST INTERNATIONAL CONFERENCE ON INFRARED AND MILLIMETER WAVES AND 14TH INTERNATIONAL CONFERENCE ON TERAHERTZ ELECTRONICS, First page：395, Last page：395, 2006, [Reviewed]
  We demonstrated terahertz imaging using a linear array detector with five elements based on superconducting tunnel junctions (STJs). Nondestructive imaging at 0.66 THz was successfully performed for a test metallic pattern and an integrated-circuit card using the STJ linear array, which shortened the total acquisition time.
  IEEE, English, International conference proceedings
  Web of Science ID：WOS:000246942200393
• Development of terahertz wave detector using superconducting tunnel junction　　　　　　　　　　　　　　　
  T Taino; K Hoshino; R Nakano; C Otani; H Myoren; K Kawase; T Shibuya; H Sato; HM Shimizu; S Takada
  PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, Volume：426, First page：1731, Last page：1735, Oct. 2005, [Reviewed]
  We have developed a new terahertz (THz) wave detector using an Nb-based superconducting tunnel junction (STJ). The STJ consists of a Nb/Al/AlOx/Al/Nb structure on a single-crystal LiNbO3 substrate. Using LiNbO3 as a substrate, an irradiating THz wave is converted to phonons in LiNbO3, which has a relatively high absorption coefficient. The phonons propagating in the substrate reach the Nb base electrode of the STJ and break Cooper pairs. As a result, the THz wave can be detected as tunneling current signals in the STJ. THz waves from a widely tunable THz-wave parametric oscillator (TPO) were irradiated on to the STJ, which acted as a THz wave detector. The STJs were cooled to an operating temperature of 0.4 K using a He-3 cryostat. We have observed STJ signals related to THz wave irradiations. In this paper, fabrication processes and characteristics of THz wave detectors using STJs are also discussed. (c) 2005 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.physc.2005.02.137
  DOI ID：10.1016/j.physc.2005.02.137, ISSN：0921-4534, Web of Science ID：WOS:000232698700153
• The effect of X-ray irradiating superconducting tunnel junctions on Al2O3 and LiNbO3 substrates　　　　　　　　　　　　　　　
  T Taino; K Hoshino; R Nakano; C Otani; H Myoren; K Kawase; H Sato; HM Shimizu; S Takada
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：15, Number：2, First page：599, Last page：601, Jun. 2005, [Reviewed]
  We have developed a phonon-mediated radiation detector using Nb-based superconducting tunnel junctions (STJs). The STJs are fabricated on a substrate as an absorber of the radiation, and a substantial amount of emergent phonons with an energy above the energy gap are detected. The performance of the detector depends on the collection efficiency of the phonons. A selection of an appropriate substrate is required for optimizing the detector performance. We fabricated Nb-based STJs on a Al2O3 and a LiNbO3 substrates, and compared the pulse heights of substrate phonon events due to X-ray irradiation to the substrates. We found that the maximum pulse height of the phonon events for the LiNbO3 substrate. was about twice of that for the Al2O3 substrate, so that these spectra which was obtained from two STJs showed different shapes, especially the peak due to phonon events.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2005.849953
  DOI ID：10.1109/TASC.2005.849953, ISSN：1051-8223, Web of Science ID：WOS:000229765300131
• Efficient fabrication process for superconducting integrated circuits using photosensitive polyimide insulation layers　　　　　　　　　　　　　　　
  K Kikuchi; M Goto; H Nakagawa; S Segawa; K Tokoro; T Taino; H Myoren; S Takada; M Aoyagi
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：15, Number：2, First page：94, Last page：97, Jun. 2005, [Reviewed]
  Photosensitive polyimide insulation layers have been introduced to fabricate superconducting integrated circuits. It is shown to simplify the fabrication process, because the photosensitive polyimide insulation layer can be patterned by conventional photolithography process, resulting in the etching process unnecessary in the present new fabrication process. Three kinds of contact hole (junction top electrode contact, junction base electrode contact, and resistor contact) are simultaneously formed in the photolithography process of the polyimide. A minimum contact hole size is designed to be 1.5 mu m square for a 3 mu m x 3 mu m squared junction. Superconducting current density of 2.4 x 10(6) A/cm(2) of the contact hole was measured. Palladium resistors were successfully made with through hole contacts of the photosensitive polyimide insulation layer. We demonstrated superconducting integrated circuits using this new fabrication process including the minimum 3 mu m x 3 mu m squared Nb/Al - AlOx/Nb Josephson tunnel junction. The circuit operation is also demonstrated in the fabricated superconducting integrated circuits with the photosensitive polyimide insulation layers.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2005.849702
  DOI ID：10.1109/TASC.2005.849702, ISSN：1051-8223, Web of Science ID：WOS:000229765300006
• X-ray detection using superconducting tunnel junctions with polyimide insulation layer　　　　　　　　　　　　　　　
  M Yoshida; K Hoshino; T Taino; H Myoren; S Takada; K Kikuchi; H Nakagawa; M Aoyagi; H Sato; HM Shimizu
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：15, Number：2, First page：606, Last page：608, Jun. 2005, [Reviewed]
  We have fabricated Nb-based superconducting tunnel junctions (STJs) with Al trapping layers using the photosensitive polyimide insulation layer for X-ray detector. It is possible to simplify the fabrication process of the STJs, because the photosensitive polyimide is used as the insulation layer instead of conventional inorganic insulation films without an etching process in a vacuum chamber. The polyimide insulation layer expects to be stable for thermal cycling between 0.3 K and room temperature. The preliminary experiments of 5.9 keV radiation shows the energy resolution of 86 eV.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2005.849955
  DOI ID：10.1109/TASC.2005.849955, ISSN：1051-8223, Web of Science ID：WOS:000229765300133
• Double relaxation oscillation SQUID with a 4JL on-chip digital flux locked-loop circuit　　　　　　　　　　　　　　　
  H Myoren; M Goto; T Taino; K Kikuchi; H Nakagawa; K Tokoro; M Aoyagi; S Takada
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：15, Number：2, First page：332, Last page：335, Jun. 2005, [Reviewed]
  Double relaxation oscillation SQUID (DROS) combined with an on-chip superconducting digital flux locked-loop (FLL) circuit has been proposed. In this study, we described superconducting digital FLL circuit which consists of an 8-bit up/down counter and an 8-bit R-2R ladder D/A converter. The circuit was designed using 4-Junction Logic (4JL)-gates which are driven by a two phase power supply. In the up/down counter, we employed binary carry lookahead (BCL) circuits for high-speed operation. Logic simulations for the BCL 8-bit up/down counter showed correct operation up to 4 GHz, assuming a 2.5 kA/cm(2) Nb/Al-AIO(x)/Nb junction technology. From simulation results high slew rate of 10(7)Phi(0)/s and dynamic range of 2.5 Phi(0) can be expected.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2005.849825
  DOI ID：10.1109/TASC.2005.849825, ISSN：1051-8223, Web of Science ID：WOS:000229765300065
• A Broad-band THz Radiation Detector using a Nb-based Superconducting Tunnel Junction　　　　　　　　　　　　　　　
  Chiko Otani
  IEEE Transactions on Applied Superconductivity, Volume：15, Number：2, First page：591, Last page：594, Jun. 2005, [Reviewed]
  We have proposed and been developing a new broad-band terahertz (THz) radiation detector using a Nb-based superconducting tunnel junction (STJ). The STJ's were fabricated on LiNbO 3 and LiTaO 3 mono-crystal substrates. We radiated monochromatic THz pulses in the range 1-2 THz with the pulse repetition rate of 49 Hz, and successfully detected the corresponding periodic signals via a charge-sensitive preamplifier. The current signal obtained by the derivative of the output signal gave the time response of about 15-20 microseconds. The frequency response was compared with that of a conventional pyro-electric sensor. We found their frequency response showed the similar shape in frequency, demonstrating the flat response of the STJ detector in 1-2 THz. These results show that the detector can be used as a broad-band THz and far-infrared radiation detector above the frequency corresponding to the energy gap of the superconductor used for the base electrode. © 2005 IEEE.
  English, Scientific journal
  DOI：https://doi.org/10.1109/TASC.2005.849950
  DOI ID：10.1109/TASC.2005.849950, ISSN：1051-8223, J-Global ID：201302272130921625, SCOPUS ID：22044458600
• Multispectral/fluorescence CT using superconducting tunnel junction detector for 3-D material analysis　　　　　　　　　　　　　　　
  Y Takizawa; H Sato; S Shiki; C Otani; M Kurakado; T Taino; HM Shimizu
  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, Volume：520, Number：1-3, First page：617, Last page：620, Mar. 2004, [Reviewed]
  We have developed superconducting tunnel junctions (STJs) for applications to astrophysics, particle physics, material physics, etc. The spectrum capability of STJs is the wide wavelength/energy range from visible light to X-ray. STJs are applicable to photon detectors with good energy resolution and a high photon-counting rate. STJs also have good efficiency because of their high absorption efficiency below 1 keV photon energy. This is advantageous in low photon emission observation like fluorescence from objects. STJs have potentials to open new windows of the Multispectral/fluorescence computed tomography (CT) below I keV photon energy. As first step, we are starting STJ-CT experiments from the high-energy X-ray region (6-20 keV). We report and discuss the CT using STJs. (C) 2003 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.nima.2003.11.330
  DOI ID：10.1016/j.nima.2003.11.330, ISSN：0168-9002, Web of Science ID：WOS:000220606900166
• Detection of single optical photons with STJ detectors in RIKEN　　　　　　　　　　　　　　　
  S Shiki; H Sato; Y Takizawa; T Taino; C Otani; HM Shimizu
  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, Volume：520, Number：1-3, First page：530, Last page：532, Mar. 2004, [Reviewed]
  We fabricated high quality Nb/Al/AlOx/Al/Nb superconducting tunnel junction (STJ) detectors in RIKEN, and succeeded detecting single optical photons. The normal resistance of the STJ device was 2 x 10(-6) Omega cm(2) and the ratio of normal resistance and dynamic resistance (Rn/Rd) at 0.2 mV was 10(-5) operated at 0.35 K. The intrinsic energy resolution for 2.64 eV(470 nm) photon was 1.0 eV. Good linearity was observed. (C) 2003 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.nima.2003.11.306
  DOI ID：10.1016/j.nima.2003.11.306, ISSN：0168-9002, Web of Science ID：WOS:000220606900142
• Response of an on-chip coil-integrated superconducting tunnel junction to x-rays　　　　　　　　　　　　　　　
  Maehata K; Taino T; Hora A; Ariyoshi T; Mori N; Ishibashi K; Matsumoto Y; Nakagawa H; Akoh H; Kikuchi K; Aoyagi M; Sato H
  JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, Volume：42, Number：5A, First page：2860, Last page：2863, May 2003, [Reviewed]
  DOI：https://doi.org/10.1143/jjap.42.2860
  DOI ID：10.1143/jjap.42.2860, ISSN：0021-4922, Web of Science ID：WOS:000183744900066
• Development of a superconducting analog-to-digital converter as a readout for high-resolution X-ray detectors based on a superconducting tunnel junction　　　　　　　　　　　　　　　
  T Oku; T Ikeda; C Otani; K Kawai; H Sato; HM Shimizu; H Miyasaka; Y Takizawa; H Watanabe; W Ootani; H Akoh; H Nakagawa; M Aoyagai; T Taino
  IEICE TRANSACTIONS ON ELECTRONICS, Volume：E85C, Number：3, First page：645, Last page：649, Mar. 2002, [Reviewed]
  We are developing a superconducting analog-to-digital converter (ADC) as a readout for high-resolution X-ray detectors based on a superconducting tunnel junction (STJ). The ADC has a sensitive front end which consists of a DC superconducting quantum interference device (SQUID). A signal current is digitized by this front end without using any preamplifiers. A single-flux-quantum (SFQ) pulse train whose frequency is proportional to the input current is launched by the front end, and integrated by a digital counter. The counter has a 10-bit resolution, and the integrated value is scanned and transferred to room-temperature processing modules with a frequency of 40 MHz. In this paper, the design of the ADC is described, and the preliminary results of the ADC performance test are shown. The performance of the STJ accompanied by the ADC is discussed in terms of the X-ray energy resolution.
  IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG, English, Scientific journal
  ISSN：0916-8524, eISSN：1745-1353, Web of Science ID：WOS:000174258200038
• A high-resolution X-ray detection system using STJ and SQUID amplifier　　　　　　　　　　　　　　　
  Ikeda T; Kato H; Sato H; Kawai K; Miyasaka H; Oku T; Ootani W; Otani C; Shimizu HM; Takizawa Y; Watanabe H; Nakagawa H; Akoh H; Aoyagi M; Taino T
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：11, Number：1, First page：704, Last page：707, Mar. 2001, [Reviewed]
  DOI：https://doi.org/10.1109/77.919442
  DOI ID：10.1109/77.919442, ISSN：1051-8223, Web of Science ID：WOS:000168285400161
• Development of superconducting tunnel junctions for ultra soft X-ray detectors　　　　　　　　　　　　　　　
  Takizawa Y; Ikeda T; Oku T; Otani C; Kawai K; Sato H; Shimizu HM; Miyasaka H; Watanabe H; Ootani W; Akou H; Nakagawa H; Aoyagi M; Taino T
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：11, Number：1, First page：721, Last page：723, Mar. 2001, [Reviewed]
  DOI：https://doi.org/10.1109/77.919446
  DOI ID：10.1109/77.919446, ISSN：1051-8223, Web of Science ID：WOS:000168285400165
• Spectral features of substrate phonon events obtained by illuminating superconducting tunnel junctions with X-rays　　　　　　　　　　　　　　　
  Otani C; Ikeda T; Kato H; Kawai K; Miyasaka H; Oku T; Ootani W; Sato H; Shimizu HM; Takizawa Y; Watanabe H; Nakagawa H; Akoh H; Aoyagi M; Taino T
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：11, Number：1, First page：708, Last page：711, Mar. 2001, [Reviewed]
  DOI：https://doi.org/10.1109/77.919443
  DOI ID：10.1109/77.919443, ISSN：1051-8223, Web of Science ID：WOS:000168285400162
• Detection of heavy ions using Nb-based superconducting tunnel junction　　　　　　　　　　　　　　　
  Sato H; Ikeda T; Kawai K; Miyasaka H; Oku T; Ootani W; Otani C; Shimizu HM; Takizawa Y; Watanabe H; Morimoto K; Tokanai F; Akoh H; Nakagawa H; Aoyagi M; Taino T
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：11, Number：1 1, First page：712, Last page：715, Mar. 2001
  English, Scientific journal
  DOI：https://doi.org/10.1109/77.919444
  DOI ID：10.1109/77.919444, ISSN：1051-8223
• High-resolution X-ray detectors based on superconducting tunnel junction with SQUID readout　　　　　　　　　　　　　　　
  T Oku; T Ikeda; H Kato; K Kawai; H Miyasaka; W Ootani; C Otani; H Sato; HM Shimizu; Y Takizawa; H Watanabe; H Nakagawa; H Akoh; M Aoyagi; T Taino
  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, Volume：444, Number：1-2, First page：136, Last page：139, Apr. 2000, [Reviewed]
  We are developing high-resolution X-ray detectors based on superconducting tunnel junctions (STJs). A two-stage superconducting quantum-interference device (SQUID) amplifier with high gain, low noise and high sensitivity was employed as a readout electronic device. We have developed the STJ readout circuit which makes it possible to optimize the STJ bias condition without disturbing the operating point of the SQUID amplifier. High-resolution X-ray detectors using our system is discussed. (C) 2000 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/S0168-9002(99)01346-7
  DOI ID：10.1016/S0168-9002(99)01346-7, ISSN：0168-9002, Web of Science ID：WOS:000086823400032
• Development of X-ray detectors based on Nb/Al/AlOx/Al/Nb superconducting tunnel junctions　　　　　　　　　　　　　　　
  W Ootani; T Ikeda; H Kato; K Kawai; H Miyasaka; T Oku; C Otani; H Sato; HM Shimizu; Y Takizawa; H Watanabe; H Nakagawa; H Akoh; M Aoyagi; T Taino
  NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT, Volume：444, Number：1-2, First page：249, Last page：252, Apr. 2000, [Reviewed]
  X-ray detectors based on Nb/Al/AlOx/Al/Nb superconducting tunnel junctions (STJ) have been fabricated. X-ray responses of the fabricated STJs were measured by illumination with X-rays from a Fe-55 electron capture source. The energy resolution of 41, 58 and 65 eV (FWHM) at 5.9 keV were obtained for 20 x 20, 100 x 100, 200 x 200 mu m(2) square-shaped devices, respectively. The X-ray measurements were performed at 0.35 K using a charge-sensitive preamplifier at room temperature. We also discussed the capability to suppress the substrate phonon events using Al2O3 insulation layer. An advantage for the combined use of the Al2O3 insulation layer and the sapphire substrate was demonstrated. (C) 2000 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/S0168-9002(99)01369-8
  DOI ID：10.1016/S0168-9002(99)01369-8, ISSN：0168-9002, Web of Science ID：WOS:000086823400056
• Properties of substrate phonon events in superconducting tunnel junctions induced by X-ray absorption　　　　　　　　　　　　　　　
  C Otani; T Ikeda; H Kato; K Kawai; H Miyasaka; T Oku; W Ootani; H Sato; HM Shimizu; Y Takizawa; H Watanabe; H Nakagawa; H Akoh; M Aoyagi; T Taino
  JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, Volume：39, Number：4A, First page：1710, Last page：1718, Apr. 2000, [Reviewed]
  The spectra of substrate phonon events induced by illuminating with X-rays obtained with Nb-based superconducting tunnel junctions (STJs) fabricated on a sapphire substrate were examined. We constructed a geometrical model in which the collection efficiency of phonons is proportional to the solid angle subtended to the Sn from the position or the absorption. By using the Monte-Carlo simulation, we succeeded in fairly reproducing the features of the spectra obtained by our measurements. A comparison of the model spectra with the measured ones revealed that a mismatch of the acoustic impedance at the junction-substrate interface and the spatial spread of a phonon cloud play an important role in the determination or the spectra. By including these effects, we show that the measured spectra can be well reproduced by adjusting only one fret, parameter, the radius of the phonon cloud. We estimated this radius in a sapphire substrate to be similar to 20 mu m under 5.9 keV X-ray illumination.
  JAPAN J APPLIED PHYSICS, English, Scientific journal
  DOI：https://doi.org/10.1143/JJAP.39.1710
  DOI ID：10.1143/JJAP.39.1710, ISSN：0021-4922, Web of Science ID：WOS:000088909200023
• Improved Fabrication Method for Nb/Al/AlOx/Al/Nb Superconducting Tunnel Junctions as X-Ray Detectors　　　　　　　　　　　　　　　
  Sato H; Takizawa Y; Ootani W; Ikeda T; Oku T; Otani C; Watanabe H; Kawai K; Miyasaka H; Kato H; Shimizu H.M; Nakagawa H; Akoh H; Aoyagi M; Taino T
  Japanese Journal of Applied Physics, Volume：39, First page：5090, Last page：5094, 2000, [Reviewed]
  Japanese, Scientific journal
  DOI：https://doi.org/10.1143/JJAP.39.5090
  DOI ID：10.1143/JJAP.39.5090
• High current transport test of a YBCO bulk conductor up to 25 kA　　　　　　　　　　　　　　　
  K Maehata; T Taino; M Mizokami; K Ishibashi; M Takeo; T Mito; A Iwamoto; S Yamada; S Satoh; O Motojima; T Shintomi; M Morita; T Tokunaga
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：9, Number：2, First page：1281, Last page：1284, Jun. 1999, [Reviewed]
  A melt-textured YBCO bulk material was employed to obtain high current transport characteristics of a bulk high temperature superconductor. A disk-shaped YBCO bulk material 65 mm in diameter and 15 mm thick was fabricated by a modified quench and melt growth (QMG) process. An "H" shaped bulk conductor was cut from the YBCO disk. The cross sectional area and length of the conductor were 7 mm x 7 mm and 20 mm, respectively. The hulk conductor was mounted in a high current bus line with a conductor-holder which allows high current feed acid mechanical support against the thermal stress and electromagnetic force. Both ends of the conductor were soldered to electrodes of the conductor-holder. At 4.2K, high current transport experiments were carried out up to 25 kA.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  ISSN：1051-8223, Web of Science ID：WOS:000081964100286
• Development of a compact system for high-resolution X-ray detection using a SQUID amplifier　　　　　　　　　　　　　　　
  T Ikeda; H Kato; K Kawai; H Miyasaka; T Oku; W Ootani; C Otani; H Sato; HM Shimizu; H Watanabe; H Nakagawa; H Akoh; M Aoyagi; T Taino
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：9, Number：2, First page：3858, Last page：3861, Jun. 1999, [Reviewed]
  A compact system for an STJ-based high resolution X-ray detection system using a SQUID amplifier has been developed. A noise level of less than 4.8 mV at the SQUID output pulse height of 1.2 V for Nb-based STJ signals was achieved in the temperature range of 1.7-4.2K with good reproducibility under an external magnetic field of about 0.01 Tesla, which was applied to suppress the Josephson current of the STJ. The results show the possibility of constructing a compact STJ-based X-ray detection system with an 'on-site' low noise SQUID preamplifier.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English, Scientific journal
  DOI：https://doi.org/10.1109/77.783869
  DOI ID：10.1109/77.783869, ISSN：1051-8223, Web of Science ID：WOS:000081964500249
• Development of Compact High-resolution X-ray Detector System using STJ and a SQUID Amplifier　　　　　　　　　　　　　　　
  T. Ikeda; H. Sato; H. Kato; K. Kawai; H. Miyasaka; T. Oku; W. Ootani; C. Ohtani; H.M. Shimizu; Y. Takizawa; H. Watanabe; H. Nakagawa; H. Akoh; M. Aoyagi; T. Taino
  Inst. Phys. Conf. Ser., Volume：167, Number：2, First page：659, Last page：662, 1999, [Reviewed]
  English, International conference proceedings

• Alpha-particle detection with airbridge implemented kinetic inductance detectors　　　　　　　　　　　　　　　
  五十嵐洋介; 成瀬雅人; 田井野徹; 明連広昭
  応用物理学会秋季学術講演会講演予稿集(CD-ROM), Volume：83rd, 2022
  ISSN：2758-4704, J-Global ID：202302252005973677
• Development of superconducting radiation detectors embedded in air bridges　　　　　　　　　　　　　　　
  和賀雄貴; 成瀬雅人; 田井野徹; 明連広昭
  応用物理学会春季学術講演会講演予稿集(CD-ROM), Volume：68th, 2021
  ISSN：2758-4704, J-Global ID：202102257503684090
• Energy resolution independent of the linewidth of superconducting microresonators for alpha particle detectors　　　　　　　　　　　　　　　
  安藤 友彦; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：119, Number：369, First page：151, Last page：153, 16 Jan. 2020
  English
  ISSN：0913-5685, CiNii Articles ID：40022155941, CiNii Books ID：AN10012885
• Design of High Timing resolution Time-to-Digital Convertor for Time-Resolving Photon Detection System using SNSPD　　　　　　　　　　　　　　　
  明連 広昭; 神谷 遼太郎; 會田 晃太; 成瀬 雅人; 田井野 徹; 康 琳; 陳 健; 呉 培亨
  Volume：119, Number：219, First page：23, Last page：26, 09 Oct. 2019
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40022064450, CiNii Books ID：AN10012885
• 高Jcプロセスを用いたSFQ論理によるディジタルSQUID磁束計の性能評価 (超伝導エレクトロニクス)　　　　　　　　　　　　　　　
  板垣 航希; 松縄 諒; 大嶋 一太; 長谷川 雄一; 成瀬 雅人; 田井野 徹; 明連 広昭; Okabe Kosuke
  Volume：119, Number：164, First page：49, Last page：53, 09 Aug. 2019
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021996943, CiNii Books ID：AN10012885
• Implementation of Digital Filter for Digital SQUID with sub-Flux Quantum Feedback Resolution　　　　　　　　　　　　　　　
  明連 広昭; 松繩 諒; 板垣 航希; 大嶋 一太; 長谷川 雄一; 成瀬 雅人; 田井野 徹
  Volume：119, Number：10, First page：33, Last page：38, 19 Apr. 2019
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021885399, CiNii Books ID：AN10012885
• Crosstalk evaluation of lumped element kinetic inductance detectors　　　　　　　　　　　　　　　
  桒田 正博; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：118, Number：415, First page：1, Last page：5, 23 Jan. 2019
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021801129, CiNii Books ID：AN10012885
• サブ磁束量子フィードバックデジタルSQUID磁束計 : 高速化・小規模回路化に関する検討 (超伝導エレクトロニクス)　　　　　　　　　　　　　　　
  板垣 航希; 大嶋 一太; 長谷川 雄一; 松縄 諒; 岡部 公亮; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：118, Number：415, First page：7, Last page：11, 23 Jan. 2019
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021801158, CiNii Books ID：AN10012885
• Comparison of photon-number-resolving detectors using superconducting nanowire　　　　　　　　　　　　　　　
  明連 広昭; 神谷 遼太郎; 傳田 哲史; 寺井 誠; 成瀬 雅人; 田井野 徹; 康 琳; 陳 健; 呉 培亨
  Volume：118, Number：233, First page：7, Last page：12, 10 Oct. 2018
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021713682, CiNii Books ID：AN10012885
• Design of sub-Flux Quantum Feedback Digital SQUID Magnetometer with First-order Sinc Filter　　　　　　　　　　　　　　　
  松縄 諒; 岡部 公亮; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：118, Number：178, First page：13, Last page：17, 09 Aug. 2018
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021657530, CiNii Books ID：AN10012885
• Superconducting resonators relying on high-Tc materials for Gamma ray detectors　　　　　　　　　　　　　　　
  成瀬 雅人; 久保田 立記; 田井野 徹; 明連 広昭
  Volume：118, Number：11, First page：23, Last page：27, 20 Apr. 2018
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021538293, CiNii Books ID：AN10012885
• Design of Digital Filter for Digital SQUID with sub-Flux Quantum Feedback Resolution　　　　　　　　　　　　　　　
  松繩 諒; 岡部 公亮; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：117, Number：428, First page：7, Last page：11, 31 Jan. 2018
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021464376, CiNii Books ID：AN10012885
• Applications of high-speed photon-number-resolving SNSPD array　　　　　　　　　　　　　　　
  明連 広昭; 大田 一喜; 傳田 哲史; 成瀬 雅人; 田井野 徹; 康 琳; 陳 健; 呉 培亨
  Volume：117, Number：223, First page：23, Last page：28, 04 Oct. 2017
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021374188, CiNii Books ID：AN10012885
• Design of Digital SQUID using sub-SFQ Feedback with High Sampling Rate　　　　　　　　　　　　　　　
  岡部 公亮; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：117, Number：171, First page：49, Last page：53, 09 Aug. 2017
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021317932, CiNii Books ID：AN10012885
• Design of Low-latency SFQ Up/Down Counter for Digital Signal Processing　　　　　　　　　　　　　　　
  神谷 遼太郎; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：117, Number：171, First page：55, Last page：59, 09 Aug. 2017
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021317973, CiNii Books ID：AN10012885
• Design and Applications of Digital SQUID Magnetometer with Sub-Flux Quantum Feedback　　　　　　　　　　　　　　　
  明連 広昭; 岡部 公亮; 神谷 遼太郎; 成瀬 雅人; 田井野 徹
  Volume：117, Number：10, First page：1, Last page：5, 21 Apr. 2017
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40021187002, CiNii Books ID：AN10012885
• Study of Magnetic shield for GroundBIRD cryostat　　　　　　　　　　　　　　　
  Kutsuma Hiroki; Semoto Munehisa; Taino Tohru; Tajima Osamu; Choi Jihoon; Damayanthi Thushara; Tomita Nozomu; Nagai Makoto; Nagasaki Taketo; Hazumi Masashi; Hattori Makoto; Ishitsuka Hikaru; Minowa Makoto; Mima Satoru; Yoshida Mitsuhiro; Kyungmin Lee; Won Eunil; Uchida Tomohisa; Otani Chiko; Oguri Shugo; Kiuchi Kenji; Koyano Ryo; Suzuki Jun'ya; Sekimoto Yutaro
  Meeting Abstracts of the Physical Society of Japan, Volume：72, Number：0, First page：504, Last page：504, 2017
  <p>宇宙マイクロ波背景放射（ＣＭＢ）偏光Ｂモード観測実験GroundBIRDは、地上から広い観測領域で高感度測定を達成し、インフレーションの解明を目指す。GroundBIRDに搭載する超伝導検出器MKIDを駆動するには地磁気の影響を十分に抑制する必要がある。現在、磁気シミュレーションや実測実験により最適な磁気シールドの設定を模索している。ここではその進捗を報告する。</p>
  The Physical Society of Japan, Japanese
  DOI：https://doi.org/10.11316/jpsgaiyo.72.1.0_504
  DOI ID：10.11316/jpsgaiyo.72.1.0_504, CiNii Articles ID：130006711454
• Photon-Number Resolving SNSPD Array with SFQ Amplifier Circuit　　　　　　　　　　　　　　　
  大田 一喜; 成瀬 雅人; 田井野 徹; 康 琳; 陳 健; 呉 培亨; 明連 広昭
  Volume：116, Number：269, First page：43, Last page：46, 26 Oct. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020991413, CiNii Books ID：AN10012885
• THz wave detection using the substrate absorption type STJ with a position resolution　　　　　　　　　　　　　　　
  曽根 雅彦; 五十嵐 直樹; 成瀬 雅人; 明連 広昭; 佐々木 芳彰; 大谷 知行; 田井野 徹
  Volume：116, Number：175, First page：1, Last page：4, 08 Aug. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020932079, CiNii Books ID：AN10012885
• Improvement of fabrication and characterization for embedded STJ　　　　　　　　　　　　　　　
  森田 浩平; 松本 功; 青柳 昌宏; 成瀬 雅人; 明連 広昭; 田井野 徹
  Volume：116, Number：175, First page：9, Last page：12, 08 Aug. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020932115, CiNii Books ID：AN10012885
• Development of the Radiation Detector Array Using High-temperature Superconductor　　　　　　　　　　　　　　　
  久保田 立記; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：116, Number：175, First page：13, Last page：17, 08 Aug. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020932118, CiNii Books ID：AN10012885
• NbN Parallel-Serial Type Superconducting Nanowire Single Photon Detector for High Speed Response　　　　　　　　　　　　　　　
  前田 優; 塩島 俊也; 成瀬 雅人; 田井野 徹; 明連 広昭
  Volume：116, Number：175, First page：41, Last page：44, 08 Aug. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020932272, CiNii Books ID：AN10012885
• Development of Broadband Microstrip Crossover for Millimeter-Wave　　　　　　　　　　　　　　　
  増田 聖; 成瀬 雅人; 田井野 徹; 明連 広昭; 関本 裕太郎; 新田 冬夢
  Volume：116, Number：175, First page：25, Last page：28, 08 Aug. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020932195, CiNii Books ID：AN10012885
• The development of the air-bridge structure of the coplanar waveguide for millimeter-wave band　　　　　　　　　　　　　　　
  伊藤 和雅; 成瀬 雅人; SHU SHIBO; 関本 裕太郎; 新田 冬夢; 田井野 徹; 明連 広昭
  Volume：116, Number：175, First page：29, Last page：33, 08 Aug. 2016
  Japanese
  ISSN：0913-5685, CiNii Articles ID：40020932221, CiNii Books ID：AN10012885
• C-8-2 Digital SQUID using DROS Comparator with Relaxation Oscillation Circuit　　　　　　　　　　　　　　　
  Kobayashi Ryota; Naruse Masato; Taino Tohru; Myoren Hiroaki
  Proceedings of the IEICE General Conference, Volume：2016, Number：2, First page：30, Last page：30, 01 Mar. 2016
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110010026112, CiNii Books ID：AN10471452
• C-8-14 Design of SFQ up/down counter for Photon-number-Resolving SNSPDs　　　　　　　　　　　　　　　
  Kumagai Kenji; Naruse Masato; Taino Toru; Myoren Hiroaki
  Proceedings of the IEICE General Conference, Volume：2016, Number：2, First page：42, Last page：42, 01 Mar. 2016
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110010026124, CiNii Books ID：AN10471452
• ミリ波帯用コプレナー導波路へのエアブリッジ構造の開発　　　　　　　　　　　　　　　
  伊藤和雅; 成瀬雅人; 田井野徹; 明連広昭; 関本裕太郎; 新田冬夢
  Volume：2016, 2016
  ISSN：1347-0639, J-Global ID：201602208492346974
• GroundBIRD: Observations of CMB polarization with fast scan modulation and MKIDs　　　　　　　　　　　　　　　
  Shugo Oguri; Jihoon Choi; Thushara Damayanthi; Makoto Hattori; Masashi Hazumi; Hikaru Ishitsuka; Kenji Kiuchi; Ryo Koyano; Hiroki Kutsuma; Kyungmin Lee; Satoru Mima; Makoto Minowa; Makoto Nagai; Taketo Nagasaki; Chiko Otani; Yutaro Sekimoto; Munehisa Semoto; Jun'ya Suzuki; Tohru Taino; Osamu Tajima; Nozomu Tomita; Eunil Won; Tomohisa Uchida; Mitsuhiro Yoshida
  Proceedings of SPIE - The International Society for Optical Engineering, Volume：9906, 2016, [Reviewed]
  © 2016 SPIE. Polarized patterns in the cosmic microwave background (CMB) radiation contains rich knowledge for early stage of the universe. In particular their odd-parity patterns at large angular scale (> 1), primordial B-modes, are smoking-gun evidence for the cosmic inflation. The GroundBIRD experiment aims to detect these B-modes with a ground-based apparatus that includes several novel devices: A high-speed rotational scan system, cold optics, and microwave kinetic inductance detectors (MKIDs). We plan to start observations in the Canary Islands in 2017. In this paper, we present the status of the development of our instruments. We established an environment that allows operation of our MKIDs in an optical configuration, in which the MKIDs observe radiations from the outside of the telescope aperture. We have also constructed MKID prototypes, and we are testing them in the optical configuration.
  SPIE-INT SOC OPTICAL ENGINEERING, English
  DOI：https://doi.org/10.1117/12.2231672
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85000899963&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85000899963&origin=inward
  DOI ID：10.1117/12.2231672, ISSN：0277-786X, eISSN：1996-756X, SCOPUS ID：85000899963, Web of Science ID：WOS:000387731100109
• NbN-based Spiral-MKIds for a sensitive terahertz imaging array　　　　　　　　　　　　　　　
  Ariyoshi Seiichiro; Nakajima Kensuke; Saito Atsushi; Taino Tohru; Yanmada Hironobu; Ohshima Shigetoshi; Otani Chiko; Bae Jongsuck; Tanaka Saburo
  Abstracts of 12th European Conference on Applied Superconductivity (EUCAS2015), First page：230, Last page：230, 2015, [Reviewed]
  English, Summary international conference
• Superconducting Microresonators for Gamma-ray Detection　　　　　　　　　　　　　　　
  NARUSE Masato; MIYAMOTO Noriaki; TAINO Tohru; MYOREN Hiroaki
  Technical report of IEICE. SCE, Volume：114, Number：247, First page：39, Last page：42, 15 Oct. 2014
  We propose a high spatial resolution gamma ray camera with superconducting resonator arrays for food screening systems. The gamma ray camera is composed of hundreds of microwave resonators. Absorbers are attached to the reverse side of the wafer. The gamma-rays create phonons in the absorber and the resonators detect the phonons propagated from the absorber. As a first step for the proposed camera, we measured 10 lumped element kinetic inductance detectors (LeKIDs) in a 0.3-K sorption cryostat. The event rate of the pixel with the Pb absorber was approximately 5 cps and 6 times higher than that of the pixel without the absorber. The rise and the fall time of events were less than the 1.1 MHz sampling of a vector network analyzer.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110009959085, CiNii Books ID：AN10012885
• NbN製力学インダクタンス検出器のテラヘルツ光学特性評価
  有吉誠一郎; 中島健介; 齊藤敦; 小川裕平; YU Xiongbin; 田井野徹; 大谷知行; 山田博信; 大嶋重利; 塚田究; 中島恵; 本下要; BAE Jongsuck
  応用物理学会秋季学術講演会講演予稿集(CD-ROM), Volume：75th, First page：ROMBUNNO.20A-A22-2, 01 Sep. 2014
  Japanese
  J-Global ID：201402285648635776
• C-8-12 Photon number resolving SNSPD detector using SQF digital SQUID readout　　　　　　　　　　　　　　　
  Takeda Shunsuke; Naruse Masato; Taino Tohru; Myoren Hiroaki; Chen Jian; Wu Peiheng
  Proceedings of the IEICE General Conference, Volume：2014, Number：2, First page：43, Last page：43, 04 Mar. 2014
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110009828254, CiNii Books ID：AN10471452
• CT-1-5 Development of an MKID Array for Two-dimensional Terahertz Spectroscopy　　　　　　　　　　　　　　　
  Ariyoshi Seiichiro; Nakajima Kensuke; Saito Atsushi; Hayashi kento; Taino Tohru; Otani Chiko; Ohshima Shigetoshi; Yu Xiogbin; Bae Jongsuck
  Proceedings of the IEICE General Conference, Volume：2014, Number：2, First page："SS, Last page：13"-"SS-15", 04 Mar. 2014
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110009828351
• MKIDsイメージングの最新動向　　　　　　　　　　　　　　　
  有吉 誠一郎; 中島 健介; 齊藤 敦; 田井野 徹; 大谷 知行
  超電導Web21, Number：2月, First page：6, Last page：8, Feb. 2014
• Design of SFQ digital circuit for photon number resolving detector using SNSPD　　　　　　　　　　　　　　　
  TAKEDA Sunsuke; NARUSE Masato; TAINO Tohru; MYOREN Hiroaki; CHEN Jian; WU Peiheng
  Technical report of IEICE. SCE, Volume：113, Number：232, First page：83, Last page：87, 02 Oct. 2013
  Superconducting nanowire single photon detectors (SNSPDs), those have a low dark count rate characteristics, fast and low jittering response, and high quantum efficiency, are expected to be used in the quantum information field and time-of-flight (TOF) mass spectrometry etc. A readout circuit using superconducting single-flux-quantum (SFQ) logic circuits has been developed to realize fast and low-jittering readout for an array of SNSPDs. SNSPDs with series-parallel meander type configurations have been demonstrated to have photon number resolving capabilities and are expected to be used for an evaluation system of single photon generators and/or an energy-dissolved fast detector for new generation TOF mass spectrometry. In this study, we present design, fabrication and confirmation of correct operations of an SFQ digital readout circuit for an SNSPD with series-parallel meander type configuration.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110009815147, CiNii Books ID：AN10012885
• Design of SFQ logic cells with magnetic shield structure for digital SQUID　　　　　　　　　　　　　　　
  Nakagawa Hironori; Naruse Masato; Taino Tohru; Myoren Hiroaki
  Proceedings of the Society Conference of IEICE, Volume：2013, Number：2, First page：25, Last page：25, 03 Sep. 2013
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110009735804, CiNii Books ID：AN10489017
• Design of SFQ circuit for photon number resolving detector using parallel SNSPD　　　　　　　　　　　　　　　
  Takeda Shunsuke; Naruse Masato; Taino Tohru; Myoren Hiroaki; Che Jian Che; Wu Peiheng
  Proceedings of the Society Conference of IEICE, Volume：2013, Number：2, First page：26, Last page：26, 03 Sep. 2013
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110009735805, CiNii Books ID：AN10489017
• Superconducting Micro-resonator arrays for High Sensitivity Terahertz-wave Cameras　　　　　　　　　　　　　　　
  NARUSE Masato; WATANABE Yoshiharu; NUNOKAWA Yuma; TAINO Tohru; MYOREN Hiroaki
  Technical report of IEICE. SCE, Volume：113, Number：11, First page：21, Last page：25, 19 Apr. 2013
  We have been developing terahertz cameras using superconducting micro-resonator arrays operated at 4K. A superconducting micro resonator, called Microwave Kinetic Inductance Detector(MKID), is one of the most sensitive detectors for terahertz wave. MKID is made from a Niobium Nitride films whose superconducting transition temperature is 15.7K with the thickness of 150nm. The film is deposited on an MgO substrate by magnetron sputtering method. To increase the number of detectors per area, we estimate the amount of microwave crosstalk between pixels with Ansys Designer. We find that the pixel crosstalk occurs by both inductive and capacitive coupling.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110009768239, CiNii Books ID：AN10012885
• Superconducting Micro-resonator arrays for High Sensitivity Terahertz-wave Cameras　　　　　　　　　　　　　　　
  NARUSE Masato; WATANABE Yoshiharu; NUNOKAWA Yuma; TAINO Tohru; MYOREN Hiroaki
  IEICE technical report. Microwaves, Volume：113, Number：12, First page：21, Last page：25, 19 Apr. 2013
  We have been developing terahertz cameras using superconducting micro-resonator arrays operated at 4K. A superconducting micro resonator, called Microwave Kinetic Inductance Detector(MKID), is one of the most sensitive detectors for terahertz wave. MKID is made from a Niobium Nitride films whose superconducting transition temperature is 15.7K with the thickness of 150nm. The film is deposited on an MgO substrate by magnetron sputtering method. To increase the number of detectors per area, we estimate the amount of microwave crosstalk between pixels with Ansys Designer. We find that the pixel crosstalk occurs by both inductive and capacitive coupling.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110009768431, CiNii Books ID：AN10013185
• スパイラル共振器を用いたマイクロ波力学インダクタンス検出器アレイの設計と評価　　　　　　　　　　　　　　　
  林 賢人; 齊藤 敦; 小川 裕平; 村田 光茂; 田中 希; 澤田 俊宏; 中島 健介; 山田 博信; 有吉 誠一郎; 田井野 徹; 田之上 寛之; 大谷 知行; 大嶋 重利
  信学技報, Volume：113, Number：11, First page：39, Last page：42, Apr. 2013
• NbN薄膜を用いたテラヘルツ帯・力学インダクタンス検出器の作製と評価
  有吉誠一郎; 中島健介; 齊藤敦; 林賢人; 田井野徹; 田之上寛之; 山田博信; 大嶋重利; 大谷知行; BAE Jongsuck
  応用物理学会春季学術講演会講演予稿集(CD-ROM), Volume：60th, First page：ROMBUNNO.28P-G10-7, 11 Mar. 2013
  Japanese
  J-Global ID：201302276643014041
• C-8-12 Coupled SQUID comparator for STJ Photon Detectors　　　　　　　　　　　　　　　
  Murashige Takuya; Naruse Masato; Taino Tohru; Myoren Hiroaki
  Proceedings of the IEICE General Conference, Volume：2013, Number：2, First page：43, Last page：43, 05 Mar. 2013
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110009767081, CiNii Books ID：AN10471452
• C-8-13 Time-Domain Multiplexing for STJ Array Detectors　　　　　　　　　　　　　　　
  Kobayashi Yuta; Sasaki Ryo; Naruse Masato; Taino Toru; Myoren Hiroaki
  Proceedings of the IEICE General Conference, Volume：2013, Number：2, First page：44, Last page：44, 05 Mar. 2013
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110009767082, CiNii Books ID：AN10471452
• テラヘルツイメージング分光のための力学インダクタンス検出器の開発　　　　　　　　　　　　　　　
  有吉 誠一郎; 中島 健介; 齊藤 敦; 田井野 徹; 大谷 知行
  超電導Web21, Number：2月, First page：3, Last page：4, Feb. 2013
• Development Status of a Microwave Kinetic Inductance Detector for an Imaging Fourier Transform Terahertz Spectrometer　　　　　　　　　　　　　　　
  ARIYOSHI Seiichiro; NAKAJIMA Kensuke; SAITO Atsushi; TAINO Tohru; OTANI Chiko
  TEION KOGAKU (Journal of Cryogenics and Superconductivity Society of Japan), Volume：47, Number：9, First page：554, Last page：561, 25 Sep. 2012
  We propose a novel microwave kinetic inductance detector (MKID) named spiral-MKID typified by a rewound spiral strip structure suitable for terahertz applications. The superconducting rewound strip works as a high-Q half wavelength microwave resonator as well as a broadband terahertz antenna. The spiral-MKIDs fabricated with NbN films reveal loaded quality factors of the order of 10⁴ at 3 K. NbN is one of the promising materials suitable for working on a convenient 4K-refrigerator. We also discuss the expected noise equivalent power of the optimized detector.
  CRYOGENICS AND SUPERCONDUCTIVITY SOCIETY OF JAPAN, Japanese
  DOI：https://doi.org/10.2221/jcsj.47.554
  DOI ID：10.2221/jcsj.47.554, ISSN：0389-2441, J-Global ID：201302222077104914, CiNii Articles ID：10030877878, CiNii Books ID：AN00333419
• 異なる基板上の窒化ニオブを用いた力学インダクタンス検出器の作製
  田之上寛之; 有吉誠一郎; 田井野徹; 古賀健祐; 古川昇; 大谷知行; 齊藤敦; 中島健介; 成瀬雅人; 明連広昭
  応用物理学会学術講演会講演予稿集(CD-ROM), Volume：73rd, First page：ROMBUNNO.14P-A2-6, 27 Aug. 2012
  Japanese
  J-Global ID：201202272309538860
• Design and Evaluation of Spiral Microwave Kinetic Inductance Detectors　　　　　　　　　　　　　　　
  中島健介; 齊藤敦; 田之上寛之; 有吉誠一郎; 田井野徹; 山田博信; 明連広昭; 大谷知行; 大嶋重利
  電子情報通信学会技術研究報告, Volume：112, Number：14(MW2012 1-8), First page：7, Last page：10, 13 Apr. 2012
  We propose a novel microwave kinetic inductance detectors named Spiral-MKIDs typified by a rewind spiral strip structure suitable for a broad band terahertz detector array application. A superconductng rewind strip works as a high-Q half wave length microwave resonator as well as a broad band antenna for terahertz light. The spiral-MKIDs fabricated with NbN thin films reveals a loaded quality factor of about 250,000 at the maximum. Broad band antenna performance of the spiral strip is confirmed by an almost constant return loss within the frequency range lower than 200GHz to higher than 2THz measured for a 100 times magnified room temperature model fabricated on a cupper foil PCB as well as numerical simulations.
  一般社団法人電子情報通信学会, Japanese
  ISSN：0913-5685, J-Global ID：201202295440909962, CiNii Articles ID：110009564267
• テラヘルツ帯2次元フーリエ分光用力学インダクタンス検出器の開発
  有吉誠一郎; 中島健介; 齊藤敦; 田井野徹; 大嶋重利; 大谷知行
  応用物理学関係連合講演会講演予稿集(CD-ROM), Volume：59th, First page：ROMBUNNO.17P-B1-2, 29 Feb. 2012
  Japanese
  J-Global ID：201202213270655786
• 窒化ニオブを用いた力学インダクタンス検出器の作製
  田之上寛之; 有吉誠一郎; 田井野徹; 古賀健祐; 古川昇; 齊藤敦; 中島健介; 明連広昭; 大谷知行
  応用物理学関係連合講演会講演予稿集(CD-ROM), Volume：59th, First page：ROMBUNNO.17P-B1-4, 29 Feb. 2012
  Japanese
  J-Global ID：201202292160234049
• Design and Fabrication of a Microwave Kinetic Inductance Detector for an Imaging Fourier Transform Terahertz Spectrometer　　　　　　　　　　　　　　　
  S. Ariyoshi; K. Nakajima; A. Saito; T. Taino; H. Tanoue; K. Koga; N. Furukawa; H. Yamada; S. Ohshima; C. Otani; J. Bae
  2012 37TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ), 2012
  We propose a novel microwave kinetic inductance detector named spiral-MKID typified by a rewind spiral strip structure suitable for terahertz applications. The superconducting rewind strip works as a high-Q microwave resonator as well as a broadband terahertz antenna. The spiral-MKIDs fabricated with NbN films reveal loaded quality factors of the order of 104 at similar to 3 K.
  IEEE, English
  DOI：https://doi.org/10.1109/IRMMW-THz.2012.6380364
  DOI ID：10.1109/IRMMW-THz.2012.6380364, ISSN：2162-2027, J-Global ID：201502821350941013, SCOPUS ID：84873477162, Web of Science ID：WOS:000330301800310
• 反射防止膜を用いたTHz波用STJ検出器の特性評価
  鈴木宏宣; 田井野徹; 有吉誠一郎; 大谷知行; 明連広昭
  応用物理学会学術講演会講演予稿集(CD-ROM), Volume：72nd, First page：ROMBUNNO.31A-W-9, 16 Aug. 2011
  Japanese
  J-Global ID：201102227274473899
• 分子線エピタキシー法によるエピタキシャル成長薄膜を用いた超伝導トンネル接合の作製
  濱尾俊幸; 有吉誠一郎; 田井野徹; 明連広昭; 古賀健祐; 大谷知行
  応用物理学会学術講演会講演予稿集(CD-ROM), Volume：72nd, First page：ROMBUNNO.31P-ZM-5, 16 Aug. 2011
  Japanese
  J-Global ID：201102262291396083
• C-8-8 Design of wide dynamic range digital SQUID with high sensitivity　　　　　　　　　　　　　　　
  Myoren Hiroaki; Terui Kosuke; Shimada Naoya; Taino Tohru
  Proceedings of the IEICE General Conference, Volume：2011, Number：2, First page：34, Last page：34, 28 Feb. 2011
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110008512447, CiNii Books ID：AN10471452
• 単結晶・超伝導トンネル接合の創製とテラヘルツ光デバイス応用
  有吉誠一郎; 濱尾俊幸; 田井野徹; 古賀健祐; 大谷知行
  エクストリームフォトニクス研究 第12回 理研・分子研合同シンポジウム 平成23年, First page：137, Last page：138, 2011
  Japanese
  J-Global ID：201202255627387062
• CT-1-5 Terahertz imaging with superconducting detectors and future prospects　　　　　　　　　　　　　　　
  Otani Chiko; Ariyoshi Seiichiro; Taino Tohru
  Proceedings of the IEICE General Conference, Volume：2010, Number：2, First page："SS, Last page：35"-"SS-36", 02 Mar. 2010
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110007875111
• テラヘルツ帯・薄膜マッチング型超伝導検出器の性能評価
  有吉誠一郎; 高橋研太; 田井野徹; 大谷知行
  エクストリームフォトニクス研究 第11回 理研・分子研合同シンポジウム 平成22年, First page：151, Last page：152, 2010
  Japanese
  J-Global ID：201102249170533982
• 基板吸収型STJを用いた大面積THz波検出器
  山下直人; 青木一隆; 渡邉穣; 石井宏和; 田井野徹; 大谷知行; 澁谷孝幸; 有吉誠一郎; 佐藤広海; 明連広昭
  応用物理学会学術講演会講演予稿集, Volume：70th, Number：1, First page：286, 08 Sep. 2009
  Japanese
  J-Global ID：200902243020402735
• 光で繋ぐ理研の基礎科学 テラヘルツ帯・薄膜マッチング型超伝導検出器の原理検証
  有吉誠一郎; 田井野徹; 大谷知行
  エクストリームフォトニクスシンポジウム-光で繋ぐ理研の基礎科学 平成21年, First page：157, Last page：158, 2009
  Japanese
  J-Global ID：201002286934246075
• Terahertz Imaging with a Two-dimensional Array Detector Based on Superconducting Tunnel Junctions　　　　　　　　　　　　　　　
  Seiichiro Ariyoshi
  Proceedings of 33rd international conference on infrared, millimeter, and terahertz waves (IRMMW-THz 2008), 31 Dec. 2008
  We demonstrated terahertz imaging using a two-dimensional array detector with 5x5 elements based on superconducting tunnel junctions. Real-time 25-pixel imaging at 0.65 THz was successfully performed. The array detector also allowed the shortening of the total acquisition time for larger images, made up of pixel blocks. ©IEEE.
  DOI：https://doi.org/10.1109/ICIMW.2008.4665736
  DOI ID：10.1109/ICIMW.2008.4665736, J-Global ID：201502854787894893, SCOPUS ID：58049093701
• 基板吸収型並列アレイSTJ検出器によるTHz波の検出
  青木一隆; 山下直人; 渡邉穣; 石井宏和; 田井野徹; 大谷知行; 渋谷孝幸; 有吉誠一郎; 佐藤広海; 明連広昭
  応用物理学会学術講演会講演予稿集, Volume：69th, Number：1, First page：249, 02 Sep. 2008
  Japanese
  J-Global ID：200902215279866337
• 超伝導トンネル接合検出器を用いたTHz波分光測定
  山下直人; 青木一隆; 渡邉穣; 石井宏和; 田井野徹; 大谷知行; 渋谷孝幸; 有吉誠一郎; 佐藤広海; 明連広昭
  応用物理学会学術講演会講演予稿集, Volume：69th, Number：1, First page：249, 02 Sep. 2008
  Japanese
  J-Global ID：200902293363389413
• 超伝導検出器2次元アレイを用いたテラヘルツイメージング
  有吉誠一郎; 大谷知行; DOBROIU A; 佐藤広海; 田井野徹; 松尾宏; 清水裕彦
  応用物理学関係連合講演会講演予稿集, Volume：55th, Number：3, First page：1168, 27 Mar. 2008
  Japanese
  J-Global ID：200902293922972264
• C-8-9 High Speed Operation of a Multiplexer for Superconducting Tunnel Junction Arrays　　　　　　　　　　　　　　　
  Yoshizawa Yu; Taino Tohru; Myoren Hiroaki; Takada Susumu
  Proceedings of the IEICE General Conference, Volume：2008, Number：2, First page：56, Last page：56, 05 Mar. 2008
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110006865619, CiNii Books ID：AN10471452
• Fabrication and Characteristics of Aluminum-based Superconducting Tunnel Junctions　　　　　　　　　　　　　　　
  KAMADA Kosuke; TAINO Tohru; SATO Hiromi; MYOREN Hiroaki; TAKADA Susumu
  IEICE technical report, Volume：107, Number：458, First page：19, Last page：22, 18 Jan. 2008
  We successfully fabricated the aluminum based superconducting tunnel junctions (Al-STJs) which used photolithography technique and dry etching process. Since it is not easy to dry etch the aluminum, we cannot form fine electrode pattern like shape of normal distribution function using the conventional reactive etching method. We took the inductively coupled plasma (ICP) on electrical discharge method and enabled dry etch the Al film. We could fabricate the Al-STJs by dry etching method with ICP. We fabricated STJ detectors with the shape of normal distribution function (σ=0.45) and junction sizes of 2,500μm^2 and 10,000μm^2. We measured I-V characteristic at 0.4K and obtained V_g=0.38mV, I_=50nA (junction size of 2,500μm^2).
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110006596209, CiNii Books ID：AN10012885
• 超伝導テラヘルツ波検出器を用いたイメージングに関する研究　　　　　　　　　　　　　　　
  田井野 徹
  Number：6(平成19年度), 2008
• 超伝導テラヘルツ波検出器を用いたイメージングに関する研究　　　　　　　　　　　　　　　
  田井野 徹
  総合研究機構研究プロジェクト研究成果報告書, Number：6(平成19年度), 2008
• Terahertz electromagnetic-wave detector using Nb-based superconducting tunnel junction on LiNbO3 substrate absorber　　　　　　　　　　　　　　　
  T. Taino; H. Ishii; S. Yoshimura; C. Otani; S. Ariyoshi; H. Myoren; K. Kawase; T. Shibuya; H. Sato; H. M. Shimizu; S. Takada
  PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, Volume：463, First page：1119, Last page：1122, Oct. 2007
  We have been developing terahertz (THz) wave detectors using superconducting tunnel junctions (STJs). The STJs consist of the Nb/ Al/AlOx/Al/Nb structure. We fabricated THz-wave detectors on LiNbO3 substrates that have a high absorption coefficient for the frequency range of 10(12) Hz. Two kinds of signals were detected when the THz-wave was irradiated from the substrate side. One was an indirect signal related to the generation of phonons. The other was a signal that corresponds to directly generated quasi-particles in the Nb electrode of the STJ. The pulse height of the indirect signal was larger than that of the latter signal. To enlarge the detector area, we designed a STJ that has different areas of the base electrode and top electrode. In this paper, the characteristics of the THz-wave detector area will be discussed. (C) 2007 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English
  DOI：https://doi.org/10.1016/j.physc.2007.03.500
  DOI ID：10.1016/j.physc.2007.03.500, ISSN：0921-4534, Web of Science ID：WOS:000250396000256
• テラヘルツ帯・薄膜マッチング型STJ検出器の原理検証
  有吉誠一郎; 田井野徹; 大谷知行; 佐藤広海; 松尾宏
  応用物理学会学術講演会講演予稿集, Volume：68th, Number：1, First page：306, 04 Sep. 2007
  Japanese
  J-Global ID：200902266335832568
• 基板吸収型並列STJアレイ検出器によるTHz検出器の高感度化
  石井宏和; 田井野徹; 大谷知行; 渋谷孝幸; 有吉誠一郎; 佐藤広海; 明連広昭; 高田進
  応用物理学会学術講演会講演予稿集, Volume：68th, Number：1, First page：305, 04 Sep. 2007
  Japanese
  J-Global ID：200902238823361325
• The structure and property of Superconducting Tunnel Junctions for Photon Detector　　　　　　　　　　　　　　　
  TAINO Tohru; WATANABE Yutaka; SATO Hiromi; MYOREN Hiroaki; TAKADA Susumu
  IEICE technical report, Volume：107, Number：171, First page：23, Last page：26, 20 Jul. 2007
  We have been fabricated superconducting tunnel junctions (STJs) for photon detector. The STJs were fabricated with three different sizes of normal-distribution-function (NDF) shape junction and five different contact-hole areas. NDF-STJs which has the dispersion parameters of 0.25, 0.15, 0.75 showed good energy resolution with small magnetic field comparing with conventional shaped STJ. The energy resolution of the STJ with different contact areas shows degradation according to increasing of contact area.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110006380837, CiNii Books ID：AN10012885
• C-8-4 Frequency Domain Multiplexing Circuit Driven by Microwave Frequency for STJ Photon Detectors Array　　　　　　　　　　　　　　　
  Naito Takuro; Taino Tohru; Myoren Hiroaki; Nakagawa Hiroshi; Aoyagi Masahiro; Takada Susumu
  Proceedings of the IEICE General Conference, Volume：2007, Number：2, First page：41, Last page：41, 07 Mar. 2007
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110006456187, CiNii Books ID：AN10471452
• 基盤吸収型テラヘルツ波検出器のイメージングに関する研究　　　　　　　　　　　　　　　
  田井野 徹; 明連 広昭; 髙田 進; 石井 宏和; 青木 一隆; 渡邉 穣; 山下 直人; 大谷 知行; 有吉 誠一郎; 佐藤 広海
  2007
• 基板吸収型テラヘルツ波検出器のイメージングに関する研究　　　　　　　　　　　　　　　
  田井野 徹; 高田 進
  Number：5(18年度), First page：103, Last page：106, 2007
• 基盤吸収型テラヘルツ波検出器のイメージングに関する研究　　　　　　　　　　　　　　　
  田井野 徹; 明連 広昭; 髙田 進; 石井 宏和; 青木 一隆; 渡邉 穣; 山下 直人; 大谷 知行; 有吉 誠一郎; 佐藤 広海
  総合研究機構研究プロジェクト成果発表会, 2007
• 基板吸収型テラヘルツ波検出器のイメージングに関する研究　　　　　　　　　　　　　　　
  田井野 徹; 高田 進
  総合研究機構研究プロジェクト研究成果報告書, Number：5(18年度), First page：103, Last page：106, 2007
• 超伝導検出器アレイを用いたテラヘルツイメージング
  有吉誠一郎; 大谷知行; ドブロユ アドリアン; 松尾宏; 佐藤広海; 田井野徹; 清水裕彦
  エクストリームフォトニクス研究-バイオイメージング 第5回理研・分子研合同シンポジウム 平成19年, First page：137, Last page：138, 2007
  Japanese
  J-Global ID：200902248710624643
• Terahertz Imaging with a Superconducting Detector Array　　　　　　　　　　　　　　　
  有吉誠一郎; 大谷知行; DOBROIU Adrian; 松尾宏; 佐藤広海; 田井野徹; 川瀬晃道; 清水裕彦
  電子情報通信学会技術研究報告, Volume：106, Number：403(ED2006 184-199), First page：59, Last page：63, 01 Dec. 2006
  Terahertz radiation is the electromagnetic range between radio waves and light waves. The imaging technology in this range is expected to generate many novel applications such as nondestructive inspection in commercial industries and security systems, medical diagnosis and astronomy. However, detector arrays for terahertz imaging are still under development, and large-scale and high-sensitivity detector arrays are acutely needed in many fields. We have designed, fabricated, and characterized a superconducting detector array using superconducting tunnel junctions (STJs) for terahertz imaging applications. The detector is composed of linearly distributed junctions placed on a superconducting microstrip line and is integrated on two wings of a log-periodic antenna. It is based on the photon-assisted tunneling process. In this paper, we explain the detector outline, performances and future prospects, and demonstrate terahertz imaging using the STJ linear array.
  一般社団法人電子情報通信学会, Japanese
  ISSN：0913-5685, J-Global ID：200902201882911281, CiNii Articles ID：110006162470
• THz波検出用基板吸収型超伝導トンネル接合素子　　　　　　　　　　　　　　　
  田井野 徹
  信学技報, Volume：106, Number：403, First page：53, Last page：57, Dec. 2006
• THz波検出のための基板吸収型STJ検出器の高感度化
  石井宏和; 吉村正太; 田井野徹; 明連広昭; 大谷知行; 渋谷孝幸; 有吉誠一郎; 佐藤広海; 延與秀人; 川瀬晃道; 高田進
  応用物理学会学術講演会講演予稿集, Volume：67th, Number：1, First page：260, 29 Aug. 2006
  Japanese
  J-Global ID：200902205818711509
• 超伝導検出器リニアアレイを用いたテラヘルツ・イメージング
  有吉誠一郎; 大谷知行; DOBROIU Adrian; 松尾宏; 佐藤広海; 田井野徹; 川瀬晃道; 清水裕彦
  応用物理学関係連合講演会講演予稿集, Volume：53rd, Number：3, First page：1185, 22 Mar. 2006
  Japanese
  J-Global ID：200902259922477324
• Development of Terahertz Imaging Array Detector using Superconducting Tunnel Junctions　　　　　　　　　　　　　　　
  大谷知行; 有吉誠一郎; 田井野徹; 川瀬晃道; 佐藤広海; 清水裕彦
  電子情報通信学会技術研究報告, Volume：105, Number：629(ED2005 238-246), First page：1, Last page：6, 23 Feb. 2006
  Diagnosis using terahertz (THz) waves holds a great potential for various applications in fields such as medicine, biology, industry and agriculture because of its transmittance to soft matters as well as the good spatial resolution. In addition, the specific spectral absorption features can be also applicable for identifying materials inside opaque packages. In many such applications, imaging measurements with high sensitivity are required to obtain precisely the distribution of the transmitted THz waves of the measured objects and to distinguish the location of the materials of interest. We are developing two types of THz detectors using Nb-based superconducting tunnel junctions. In this paper, we introduce their detection principles, performances, and recent results including THz imaging.
  一般社団法人電子情報通信学会, Japanese
  ISSN：0913-5685, J-Global ID：200902209427033226, CiNii Articles ID：110004678650
• Direct and indirect detection of terahertz waves using a Nb-based superconducting tunnel junction　　　　　　　　　　　　　　　
  Otani, Chiko; Shibuya, Takayuki; Ariyoshi, Seiichiro; Sato, Hiromi; Shimizu, Hirohiko M.; Kawase, Kodo; Nakano, Ran; Taino, Tohru; Yoshimura, Shota; Myoren, Hiroaki; Takada, Susumu
  Volume：43, Number：1, 2006
  ISSN：1742-6588, J-Global ID：201902204323821171
• Frequency-Division Multiplexed Readout for STJ Array Detectors　　　　　　　　　　　　　　　
  HAMAMOTO Wataru; NAITO Takuro; TAINO Tohru; MYOREN Hiroaki; TAKADA Susumu
  Technical report of IEICE. SCE, Volume：105, Number：210, First page：17, Last page：20, 20 Jul. 2005
  We proposed a readout circuit of Superconducting Tunnel Junction (STJ) array detectors. The proposed circuit based on a frequency-division multiplexed readout by applied AC bias current of different frequency to array STJs. An STJ was placed in a balanced bridge circuit, connected a resonance circuit for select output frequency. When photons irradiates to the array STJ, the output signals are frequency multiplexed in an output signal line. We designed a circuit consists of two STJs which output frequencies of 20MHz and 40MHz, respectively. We have successfully confirmed its correct operations using the JSPICE3 superconducting circuit simulator.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110003224608, CiNii Books ID：AN10012885
• CS-7-3 THz DETECTOR USING STJ WITH SUBSTRATE ABSORBER　　　　　　　　　　　　　　　
  Myoren Hiroaki; Nakano Ran; Hoshino Koichi; Yoshimura Shota; Taino Tohru; Otani Chiko; Shibuya Takayuki; Sato Hiromi; Shimizu Hirohiko M; Takada Susumu; Kawase Kodo
  Proceedings of the IEICE General Conference, Volume：2005, Number：2, First page："S, Last page：13"-"S-14", 07 Mar. 2005
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110004740861
• 基板吸収型超伝導トンネル接合素子によるTHz波検出<論文>　　　　　　　　　　　　　　　
  中野 蘭; 田井野 徹; 明連 広昭; 高田 進
  Volume：1, Number：38, First page：18, Last page：21, 2005
• AI系STJ素子を用いた超高性能フォトン検出器の作製に関する研究　　　　　　　　　　　　　　　
  田井野 徹
  Volume：16年度, 2005
• 基板吸収型超伝導トンネル接合素子によるTHz波検出<論文>　　　　　　　　　　　　　　　
  中野 蘭; 田井野 徹; 明連 広昭; 高田 進
  埼玉大学紀要, 工学部, 第1部論文集, Volume：1, Number：38, First page：18, Last page：21, 2005
• AI系STJ素子を用いた超高性能フォトン検出器の作製に関する研究　　　　　　　　　　　　　　　
  田井野 徹
  総合研究機構研究プロジェクト研究成果報告書, Volume：16年度, 2005
• Terahertz detector using a Nb-based superconducting tunnel junction　　　　　　　　　　　　　　　
  C. Otani; K. Hoshino; T. Taino; H. Myoren; R. Nakano; S. Ariyoshi; H. Sato; H. M. Shimizu; S. Takada; K. Kawase
  Conference Digest of the 2004 Joint 29th International Conference on Infrared and Millimeter Waves and 12th International Conference on Terahertz Electronics, First page：243, Last page：244, 01 Dec. 2004
  We have developed a terahertz (THz) radiation detector using a Nb-based superconducting tunnel junction (STJ). The STJ was fabricated on a stoichiometric LiNbO 3 substrate. The incident THz photons absorbed by the substrate generate THz phonons, and a substantial amount of the phonons are detected by the STJ. The detector is expected to be sensitive to a wideband THz/far-infrared radiation above the energy gap of the Mb superconductor. We radiated monochromatic nanosecond THz pulses with the repetition rate of 49 Hz, and detected the corresponding periodic signals for the 1.1-1.9 THz radiation. ©2004 IEEE.
  SCOPUS ID：20144386844
• 超伝導トンネル接合素子を用いた基板吸収型テラヘルツ波検出器の開発 (II)
  大谷知行; 田井野徹; 中野蘭; 明連広昭; 有吉誠一郎; 佐藤広海; 清水裕彦; 川瀬晃道
  応用物理学会学術講演会講演予稿集, Volume：65th, Number：3, First page：980, 01 Sep. 2004
  Japanese
  J-Global ID：200902203431997126
• β-Taトラッピング層をもつNb系超伝導トンネル素子を用いたフォトン検出器　　　　　　　　　　　　　　　
  明連 広昭; 田井野 徹; 高田 進
  Number：37, First page：3, Last page：8, Mar. 2004
  Japanese
  ISSN：0916-6394, CiNii Articles ID：40006332164, CiNii Books ID：AN00095740
• Wideband photon detector using STJ on substrate for absorber　　　　　　　　　　　　　　　
  HOSHINO Kouichi; TAINO Tohru; MYOREN Hiroaki; OTANI Chiko; SATO Hiromi; KAWASE Kodo; SHIMIZU Hirohiko M; TAKADA Susumu
  Technical report of IEICE. SCE, Volume：103, Number：592, First page：1, Last page：4, 16 Jan. 2004
  We have proposed and fabricated superconducting runnel junction on LiNbO_3 substrate for high speed and wide energy band photon detector. The characteristic of this STJ on LiNbO_3 was equivalent to conventional STJ, which was fabricated on sapphire substrate. Phonons produced by irradiating 5.9keV X-ray at the surface of LiNbO_3 were detected by the STJ. Comparing spectrum of two STJ, phonons produced in LiNbO_3 substrate showed high energy absorption.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  ISSN：0913-5685, CiNii Articles ID：110003174288
• On-chip coil-integrated STJ using the persistent superconducting current for photon detectors　　　　　　　　　　　　　　　
  K Kikuchi; T Taino; M Nanme; H Nakagawa; M Aoyagi; H Sato; H Akoh; T Iizuka; H Myoren; S Takada; K Maehata; K Ishibashi; H Sato; T Ikeda; C Otani; Y Takizawa; T Oku; K Kawai; H Miyasaka; HM Shimizu; H Kato; H Watanabe
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：13, Number：2, First page：1132, Last page：1135, Jun. 2003
  A superconducting tunnel junction (STJ) is very attractive for use in high-energy-resolution photon detectors because. of its small energy gap. To detect a single photon, the Josephson current of the STJ has had to be suppressed by an external magnetic field. We demonstrated an on-chip coil-integrated STJ photon detector, which excludes the external magnetic field, allowing a small device size. A normal-distribution function shape was adopted for the superconducting electrodes, which makes the magnetic field supplied to the STJ small. We devise a new superconducting, photon detector by combining the above techniques. A new Josephson switching gate is also integrated on the same detector chip in order to drive an on-chip integrated coil by a persistent superconducting current. This behavior was confirmed experimentally using the technology of the fabrication process of the Nb/Al-AlOx/Nb Josephson tunnel junction.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English
  DOI：https://doi.org/10.1109/TASC.2003.814173
  DOI ID：10.1109/TASC.2003.814173, ISSN：1051-8223, Web of Science ID：WOS:000184241700263
• 超伝導トンネル接合素子を用いた近赤外~可視~紫外~極端紫外域の一光子分光検出器の開発(IV)
  志岐成友; 田井野徹; 佐藤広海; 滝澤慶之; 大谷知行; 清水裕彦; 有吉誠一郎
  日本天文学会年会講演予稿集, Volume：2003, First page：197, 2003
  Japanese
  ISSN：1347-0639, J-Global ID：201302224566150875
• 超伝導トンネル接合素子を用いた近赤外~可視~紫外~極端紫外域の一光子分光検出器の開発(VI)
  志岐成友; 佐藤広海; 滝澤慶之; 大谷知行; 清水裕彦; 田井野徹; 有吉誠一郎
  日本天文学会年会講演予稿集, Volume：2003, First page：219, 2003
  Japanese
  ISSN：1347-0639, J-Global ID：201302286070507957
• X-ray detection by an on-chip coil integrated superconducting tunnel junction　　　　　　　　　　　　　　　
  MAEHATA K; ARIYOSHI T; HORA A; TAINO T; SATO H; NAKAGAWA H; KIKUCHI K; AOYAGI M; MATSUMOTO Y
  Volume：74, Number：7, First page：3258, Last page：3262, 2003
  DOI：https://doi.org/10.1063/1.1578155
  DOI ID：10.1063/1.1578155, ISSN：0034-6748, CiNii Articles ID：80016045272
• 超伝導トンネル接合素子を用いて可視光の一光子分光に成功
  志岐成友; 佐藤広海; 滝澤慶之; 大谷知行; 清水裕彦; 田井野徹; 有吉誠一郎
  日本天文学会年会講演予稿集, Volume：2003, First page：274, 2003
  Japanese
  ISSN：1347-0639, J-Global ID：201302297993581043
• 陽極酸化法による超伝導トンネル接合X線検出器の作製と特性
  田井野徹; 佐藤広海; 滝沢慶之; 志岐成友; 大谷知行; 清水裕彦; 有吉誠一郎
  応用物理学会学術講演会講演予稿集, Volume：63rd, Number：1, First page：233, 24 Sep. 2002
  Japanese
  J-Global ID：200902188511914150
• On-chip coil integrated superconducting tunnel junction for a high performance X-ray detector　　　　　　　　　　　　　　　
  T Taino; K Kikuchi; M Nanme; H Nakagawa; M Aoyagi; H Sato; H Akoh; K Maehata; K Ishibashi; H Sato; C Otani; T Ikeda; T Oku; H Kato; K Kawai; H Miyasaka; Y Takizawa; H Watanabe; HM Shimizu
  PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, Volume：372, First page：403, Last page：406, Aug. 2002
  On-chip coil integrated superconducting tunnel junction (OC2-STJ) has been demonstrated for high performance Xray detector. The STJ was fabricated by an improved fabrication technique based on a high quality Nb/Al/AlOx/Nb junction technology. The STJ shows high quality current-voltage characteristics with an ultra-low leakage current of a few nA at 0.4 K for 100 mum x 100 mum junction. Typical critical current of the coil was achieved more than 50 mA for 2 mum line width, which can generate a magnetic field of about 10 mT into the STJ. It was found that the OC2-STJ successfully responded to the irradiated 5.9 keV X-ray. (C) 2002 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English
  DOI：https://doi.org/10.1016/S0921-4534(02)00710-4
  DOI ID：10.1016/S0921-4534(02)00710-4, ISSN：0921-4534, Web of Science ID：WOS:000177936400098
• 超伝導トンネル接合素子を用いた近赤外~可視~紫外~極端紫外域の一光子分光検出器の開発(IV)
  志岐成友; 田井野徹; 佐藤広海; 滝澤慶之; 大谷知行; 清水裕彦; 有吉誠一郎
  日本天文学会年会講演予稿集, Volume：2002, First page：242, 2002
  Japanese
  ISSN：1347-0639, J-Global ID：201402117673919070
• Operation test system of superconducting tunnel junction photon detectors using a compact 3He-4He dilution refrigerator　　　　　　　　　　　　　　　
  K. Maehata; T. Taino; Y. Kawasaki; A. Hora; T. Ariyoshi; K. Ishibashi; T. Umeno; Y. Kamioka; H. Sato
  Proceedings of Focused on Development and Application of Superconducting Radiation Detector (RIKEN Review No.47), First page：24, Last page：27, 2002
• A microstrip-coil integration on superconducting tunnel junctions for X-ray detection　　　　　　　　　　　　　　　
  T Taino; H Nakagawa; M Aoyagi; H Sato; H Akoh; K Maehata; K Ishibashi; H Sato; T Ikeda; C Otani; W Ootani; T Oku; H Kato; K Kawai; HM Shimizu; Y Takizawa; H Miyasaka; H Watanabe
  IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, Volume：11, Number：1, First page：700, Last page：703, Mar. 2001
  We report the first demonstration of X-ray detection by using a Superconducting Tunnel Junction (STJ) with a microstrip-coil, The STJ was fabricated based on Nb/AYAlO(x)/Nb integration process technology using a 2(m)(mu) design rule. Magnetic field was applied into the STJ by the microstrip-coil to suppress the de Josephson current instead of the conventional electromagnet, The output waveform was successfully observed by irradiation of 5.9 keV X-ray under a condition of microstrip-coil current of 20 mA at 0.4 K.
  IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, English
  DOI：https://doi.org/10.1109/77.919441
  DOI ID：10.1109/77.919441, ISSN：1051-8223, eISSN：1558-2515, Web of Science ID：WOS:000168285400160
• 可視光天文学への応用　　　　　　　　　　　　　　　
  大谷知行; 池田時浩; 奥隆之; 渡辺博; 大谷航; 仲川博; 赤穂博司; 青柳昌宏; 田井野徹
  STJ Workshop集録, Volume：2nd, First page：164, Last page：180, 31 Jan. 2001
  Japanese
  J-Global ID：200902181441867251
• A Microstrip-coil Integration on Superconducting Tunnel Junctions for X-ray Detector　　　　　　　　　　　　　　　
  IEEE Transactions on Applied Superconductibity, Volume：11, Number：1, First page：700, Last page：703, 2001
  DOI：https://doi.org/10.1109/77.919441
  DOI ID：10.1109/77.919441
• 超伝導トンネル接合素子の漏れ電流抑制のための新手法とその効果　　　　　　　　　　　　　　　
  佐藤広海; 池田時浩; 大谷知行; 大谷航; 奥隆之; 加藤博; 川井和彦; 清水裕彦; 滝沢慶之; 宮坂浩正; 渡辺博; 赤穂博司; 青柳昌宏; 仲川博; 田井野徹
  応用物理学関係連合講演会講演予稿集, Volume：47th, Number：1, First page：259, 28 Mar. 2000
  Japanese
  J-Global ID：201202134579450316
• 超伝導トンネル接合素子で得られたX線スペクトル中の基板フォノン構造の起源　　　　　　　　　　　　　　　
  大谷知行; 池田時浩; 大谷航; 奥隆之; 加藤博; 川井和彦; 佐藤広海; 清水裕彦; 滝沢慶之; 宮坂浩正; 渡辺博; 仲川博; 赤穂博司; 青柳昌宏; 田井野徹
  応用物理学関係連合講演会講演予稿集, Volume：47th, Number：1, First page：260, 28 Mar. 2000
  Japanese
  J-Global ID：201202147363835293
• A Superconducting Tunnel Junction with Superconducting Microstrip Coil for X-ray Detector　　　　　　　　　　　　　　　
  Volume：2, First page：675, Last page：678, 2000
• A Superconducting Tunnel Junction with Superconducting Microstrip Coil for X-ray Detector　　　　　　　　　　　　　　　
  Applied Superconductivity, Volume：2, First page：675, Last page：678, 2000
• 26pYA-9 Development of X-ray Delection System with Superconducting Tunnel Junctions (VII)　　　　　　　　　　　　　　　
  Ikeda Tokihiro; Ootani W; Kato H; Kawai K; Matsuoka M; Miyasaka H; Oku T; Otani C; Sato H; Shimizu H.M; Takizawa Y; Watanabe H; Ako H; Aoyagi M; Nakagawa H; Takada S; Kino Y; Inaba K; Ishibashi K; Maehata K; Taino T
  Meeting abstracts of the Physical Society of Japan, Volume：54, Number：2, 03 Sep. 1999
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110001994794
• 超伝導トンネル接合素子を用いた高分解能X線検出器の開発　　　　　　　　　　　　　　　
  佐藤広海; 池田時浩; 大谷知行; 大谷航; 渡辺博; 赤穂博司; 青柳昌宏; 仲川博; 田井野徹
  応用物理学関係連合講演会講演予稿集, Volume：46th, Number：1, First page：279, 28 Mar. 1999
  Japanese
  J-Global ID：200902197789995885
• 28a-YK-6 Development of X-ray Detection System with Superconducting Tunnel Junctions(VI)　　　　　　　　　　　　　　　
  Otani C; Ikeda T; Kato H; Kawai K; Matsuoka M; Miyasaka H; Oku T; Sato H; Shimizu H.M; Watanabe H; Ako H; Aoyagi M; Nakagawa H; Takada S; Kino Y; Inaba K; Ishibashi K; Maehata K; Taino T
  Meeting abstracts of the Physical Society of Japan, Volume：54, Number：1, 15 Mar. 1999
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110002145620
• 30p-XJ-10 Development of X-ray Detection System with Superconducting Tunnel Junctions (IV)　　　　　　　　　　　　　　　
  Ikeda Tokihiro; Otani C; Kato H; Kawai K; Matsuoka M; Miyasaka H; Oku T; Sato H; Shimizu H.M; Watanabe H; Ako H; Aoyagi M; Nakagawa H; Sato H; Takada S; Kino Y; Inaba K; Ishibashi K; Maehata K; Taino T
  Meeting abstracts of the Physical Society of Japan, Volume：54, Number：1, 15 Mar. 1999
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110002221001
• Fabrication of Superconducting Tunnel Junction with Magnetic Coil for X-ray Detector　　　　　　　　　　　　　　　
  Taino T; Nakagawa H; Aoyagi M; Akoh H; Maehata K; Ishibashi K; Sato H; Ikeda T; Otani C; Ootani W; Oku T; Kato H; Kawai K; Shimizu M.H; Takizawa H; Miyasaka H; Watanabe H
  Technical report of IEICE. SCE, Volume：98, Number：564, First page：43, Last page：48, 27 Jan. 1999
  The superconducting coil integrated on the superconducting tunnel junction(STJ)has been designed and fabricated to suppress the Josephson current for applying an X-ray detector. The I-V characteristics and Fraunhofer characteristics were measured under the magnetic fields of the superconducting coil and an external conventional coil. Characteristic features under the magnetic fields of both coils were quite similar. The suppression of both Josephson current and Fisk step were achieved using the present superconducting coil integrated on the STJ at 4.2K.
  The Institute of Electronics, Information and Communication Engineers, Japanese
  CiNii Articles ID：110003187497
• Development of X-ray Detection System with Superconducting Tunnel Junctions(III)　　　　　　　　　　　　　　　
  IKEDA Tokihiro; OTANI C; KATO H; KAWAI K; MATSUOKA M; MIYASAKA H; OKU T; SATO H; SHIMIZU H.M; WATANABE H; AKO H; AOYAGI M; NAKAGAWA H; TAKADA S; KINO Y; INABA K; ISHIBASHI K; MAEHATA K; TAINO T
  Meeting abstracts of the Physical Society of Japan, Volume：53, Number：2, 05 Sep. 1998
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110002057115
• Large-area tunnel junction exhibiting two operating modes for X-ray detection　　　　　　　　　　　　　　　
  T Taino; K Ishibashi; K Maehata; S Yoshida; ML Povinelli; H Nakagawa; H Akoh; K Joosse; S Takada; M Kishimoto; M Katagiri
  JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, Volume：37, Number：2, First page：25, Last page：30, 1998
  High quality Nb-based tunnel junctions with surface areas of 100 x 100 mu m(2) and 200 x 200 mu m(2) were tested by irradiating x-rays. The 200 x 200 mu m(2) junction exhibited better x-ray response than that of the 100 x 100 mu m(2) one, due to better collection of quasiparticles. The junction detected 5.9-keV x-rays with an energy resolution (FWHM) of 93 eV and the energy required for single electron collection was 6.5 meV. In the operation of the 200 x 200 mu m(2) junction, two kinds of operation modes with different pulse heights were found by applying a magnetic field with different ramping speeds. The individual operation modes gave different current-voltage characteristics. The Sine-Gordon equation was employed to calculate the current-voltage characteristics for the large junction. From calculated results, it was confirmed that the higher pulse height operation mode was related to a large reduction of de current through the junction.
  JAPAN J APPLIED PHYSICS, English
  ISSN：0021-4922, Web of Science ID：WOS:000076543000008

• -

• テラヘルツ波検出器の開発　　　　　　　　　　　　　　　
  Competitive research funding
• フォトン検出器の開発　　　　　　　　　　　　　　　
  Competitive research funding
• Development of terahertz wave detector　　　　　　　　　　　　　　　
  Competitive research funding
• Development of photon detector　　　　　　　　　　　　　　　
  Competitive research funding