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Author |
Smirnov, K.; Divochiy, A.; Vakhtomin, Y.; Morozov, P.; Zolotov, P.; Antipov, A.; Seleznev, V. |
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Title |
NbN single-photon detectors with saturated dependence of quantum efficiency |
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Journal Article |
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Year |
2018 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
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Volume |
31 |
Issue |
3 |
Pages |
035011 (1 to 8) |
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Keywords |
NbN SSPD, SNSPD |
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Abstract |
The possibility of creating NbN superconducting single-photon detectors with saturated dependence of quantum efficiency (QE) versus normalized bias current was investigated. It was shown that the saturation increases for the detectors based on finer films with a lower value of Rs300/Rs20. The decreasing of Rs300/Rs20 was related to the increasing influence of quantum corrections to conductivity of superconductors and, in turn, to the decrease of the electron diffusion coefficient. The best samples have a constant value of system QE 94% at Ib/Ic ~ 0.8 and wavelength 1310 nm. |
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0953-2048 |
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1232 |
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Antipov, S.; Trifonov, A.; Krause, S.; Meledin, D.; Kaurova, N.; Rudzinski, M.; Desmaris, V.; Belitsky, V.; Goltsman, G. |
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Title |
Improved bandwidth of a 2 THz hot-electron bolometer heterodyne mixer fabricated on sapphire with a GaN buffer layer |
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Journal Article |
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Year |
2019 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
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Volume |
32 |
Issue |
7 |
Pages |
075003 |
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Keywords |
NbN HEB mixer, GaN buffer layer, sapphire substrate |
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Abstract |
We report on the signal-to-noise and gain bandwidth of a niobium nitride (NbN) hot-electron bolometer (HEB) mixer at 2 THz fabricated on a sapphire substrate with a GaN buffer layer. Two mixers with different DC properties and geometrical dimensions were studied and they demonstrated very close bandwidth performance. The signal-to-noise bandwidth is increased to 8 GHz in comparison to the previous results, obtained without a buffer-layer. The data were taken in a quasi-optical system with the use of the signal-to-noise method, which is close to the signal levels used in actual astrophysical observations. We find an increase of the gain bandwidth to 5 GHz. The results indicate that prior results obtained on a substrate of crystalline GaN can also be obtained on a conventional sapphire substrate with a few micron MOCVD-deposited GaN buffer-layer. |
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IOP Publishing |
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Antipov_2019 |
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1277 |
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Author |
Yang, Z. Q.; Hajenius, M.; Baselmans, J. J. A.; Gao, J. R.; Voronov, B.; Gol’tsman, G. N. |
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Title |
Reduced noise in NbN hot-electron bolometer mixers by annealing |
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Journal Article |
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Year |
2006 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
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Volume |
19 |
Issue |
4 |
Pages |
L (9 to 12) |
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Keywords |
NbN HEB mixers |
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Abstract |
We find that the sensitivity of heterodyne receivers based on superconducting hot-electron bolometers (HEBs) increases by 25–30% after annealing at 85 °C in vacuum. The devices studied are twin-slot antenna coupled mixers with a small NbN bridge of 1 × 0.15 µm2. We show that annealing changes the device properties as reflected in sharper resistive transitions of the complete device, apparently reducing the device-related noise. The lowest receiver noise temperature of 700 K is measured at a local oscillator frequency of 1.63 THz and a bath temperature of 4.3 K. |
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0953-2048 |
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1456 |
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Author |
Lipatov, A.; Okunev, O.; Smirnov, K.; Chulkova, G.; Korneev, A.; Kouminov, P.; Gol'tsman, G.; Zhang, J.; Slysz, W.; Verevkin, A.; Sobolewski, R. |
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Title |
An ultrafast NbN hot-electron single-photon detector for electronic applications |
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Journal Article |
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Year |
2002 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
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Volume |
15 |
Issue |
12 |
Pages |
1689-1692 |
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Keywords |
NbN SSPD, SNSPD, QE, jitter, dark counts |
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Abstract |
We present the latest generation of our superconducting single-photon detector (SPD), which can work from ultraviolet to mid-infrared optical radiation wavelengths. The detector combines a high speed of operation and low jitter with high quantum efficiency (QE) and very low dark count level. The technology enhancement allows us to produce ultrathin (3.5 nm thick) structures that demonstrate QE hundreds of times better, at 1.55 μm, than previous 10 nm thick SPDs. The best, 10 × 10 μm2, SPDs demonstrate QE up to 5% at 1.55 μm and up to 11% at 0.86 μm. The intrinsic detector QE, normalized to the film absorption coefficient, reaches 100% at bias currents above 0.9 Ic for photons with wavelengths shorter than 1.3 μm. |
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0953-2048 |
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Call Number |
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Serial |
1533 |
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Author |
Il'in, K. S.; Verevkin, A. A.; Gol'tsman, G. N.; Sobolewski, R. |
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Title |
Infrared hot-electron NbN superconducting photodetectors for imaging applications |
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Journal Article |
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Year |
1999 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
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Volume |
12 |
Issue |
11 |
Pages |
755-758 |
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Keywords |
NbN SSPD, SNSPD |
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Abstract |
We report an effective quantum efficiency of 340, responsivity >200 A W-1 (>104 V W-1) and response time of 27±5 ps at temperatures close to the superconducting transition for NbN superconducting hot-electron photodetectors (HEPs) in the near-infrared and optical ranges. Our studies were performed on a few nm thick NbN films deposited on sapphire substrates and patterned into µm-size multibridge detector structures, incorporated into a coplanar transmission line. The time-resolved photoresponse was studied by means of subpicosecond electro-optic sampling with 100 fs wide laser pulses. The quantum efficiency and responsivity studies of our photodetectors were conducted using an amplitude-modulated infrared beam, fibre-optically coupled to the device. The observed picosecond response time and the very high efficiency and sensitivity of the NbN HEPs make them an excellent choice for infrared imaging photodetectors and input optical-to-electrical transducers for superconducting digital circuits. |
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0953-2048 |
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1562 |
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Author |
Rönnung, F.; Cherednichenko, S.; Winkler, D.; Gol'tsman, G. N. |
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Title |
A nanoscale YBCO mixer optically coupled with a bow tie antenna |
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Journal Article |
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Year |
1999 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
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Volume |
12 |
Issue |
11 |
Pages |
853-855 |
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Keywords |
YBCO HTS HEB mixers |
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Abstract |
The bolometric response of YBa2Cu3O7-δ(YBCO) hot-electron bolometers (HEBs) to near-infrared radiation was studied. Devices were fabricated from a 50 nm thick film and had in-plane areas of 10 × 10 µm2, 2 × 0.2 µm2, 1 × 0.2µm2 and 0.5 × 0.2 µm2. We found that nonequilibrium phonons cool down more effectively for the bolometers with smaller area. For the smallest bolometer the bolometric component in the response is 10 dB less than for the largest one. |
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0953-2048 |
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1563 |
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Author |
Danerud, M.; Winkler, D.; Lindgren, M.; Zorin, M.; Trifonov, V.; Karasik, B.; Gershenzon, E. M.; Gol'tsman, G. N. |
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Title |
A fast infrared detector based on patterned YBCO thin film |
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Journal Article |
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Year |
1994 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
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Volume |
7 |
Issue |
5 |
Pages |
321-323 |
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Keywords |
YBCO HTS detector |
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Abstract |
Detectors for infrared radiation ( lambda =0.85 mu m) were made of 50 nm thick YBa2Cu3O7- delta films on LaAlO3 and MgO or 60 nm thick films on NdGaO3. Parallel strips (1 mu m wide by 20 mu m long) were patterned in the films and formed the active device. These devices were designed to detect short infrared laser pulses by electron heating. The detectors were current biased into the resistive and the normal states. The response was studied in direct pulse measurements as well as by amplitude modulation of a laser. The pulse measurements showed a fast picosecond response followed by a slower decay related to phonon escape through the film-substrate interface and heat diffusion in the substrate. The frequency spectra up to 10 GHz showed two slopes with a knee corresponding to the phonon escape time. |
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0953-2048 |
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no |
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1646 |
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Author |
Verevkin, A. A.; Ptitsina, N. G.; Chulcova, G. M.; Gol'tsman, G. N.; Gershenzon, E. M.; Yngvesson, K. S. |
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Title |
Direct measurements of energy relaxation time of electrons in AlGaAs/GaAs heterostructures under quasi-equilibrium conditions |
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Journal Article |
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Year |
1996 |
Publication |
Surface Science |
Abbreviated Journal |
Surface Science |
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361-362 |
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569-573 |
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Keywords |
2DEG, AlGaAs/GaAs heterostructures |
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For the first time, results are presented of a direct measurement of the energy relaxation time τε of 2D electrons in an AlGaAs/GaAs heterojunction at T = 1 and 5–20 K. A weak temperature dependence of τε for the T > 4K range and a linear temperature dependence of the reciprocal of τε for T < 4K have been observed. The linear dependence τε−1 ≈ T in the Bloch-Gruneisen regime is direct evidence of the predominance of the piezo-electric mechanism of electron-phonon interaction in non-elastic electron scattering processes. The values of τε in this regime are in very good agreement with the results of the Karpus theory. At higher temperatures, where the deformation-potential scattering becomes noticeable, a substantial disagreement between the experimental data and the theoretical results is observed. |
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ISSN |
0039-6028 |
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no |
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Call Number |
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Serial |
1609 |
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Author |
Voronov, B. M.; Gershenzon, E. M.; Gol'tsman, G. N.; Gubkina, T. O.; Semash, V. D. |
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Title |
Superconductive properties of ultrathin NbN films on different substrates |
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Journal Article |
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Year |
1994 |
Publication |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
Abbreviated Journal |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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Volume |
7 |
Issue |
6 |
Pages |
1097-1102 |
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Keywords |
NbN films |
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A study was made on dependence of surface resistance, critical temperature and width of superconducting transition on application temperature and thickness of NbN films, which varied within the range of 3-10 nm. Plates of sapphire, fused and monocrystalline quartz, MgO, as well as Si and silicon oxide were used as substrates. NbN films with 160 μθ·cm specific resistance and 16.5 K (Tc) critical temperature were obtained on sapphire substrates. Intensive growth of ΔTc was noted for films, applied on fused quartz, with increase of precipitation temperature. This is explained by occurrence of high tensile stresses in NbN films, caused by sufficient difference of thermal coefficients of expansion of NbN and quartz. |
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Russian |
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0131-5366 |
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Сверхпроводниковые свойства ультратонких пленок NbN на различных подложках |
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1631 |
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Author |
Gershenzon, E.M.; Gol'tsman, G.N.; Dzardanov, A.L.; Kuznetsov, E.A. |
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Title |
Superconducting UHF-limiter based on electron heating up |
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Journal Article |
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Year |
1992 |
Publication |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
Abbreviated Journal |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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Volume |
5 |
Issue |
11 |
Pages |
2164-2170 |
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Keywords |
electron heating, applications |
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The results of experimental investigation of fast-action 5HF-limiter are presented; the limiter is based on the utilization of electron hetaing phenomenon in thin superconducting films. The design of SHF-limiter, which is intended for operation at liquid helium temperatures and which has the form of a section of superconducting NbN microstrip line for 1-12 GHz rang, is described. |
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Russian |
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0235-8964 |
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1669 |
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Voronov, B. M.; Gershenzon, E. M.; Gol'tsman, G. N.; Gogidze, I. G.; Gusev, Yu. P.; Zorin, M. A.; Sejdman, L. A.; Semenov, A. D. |
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Title |
Picosecond range detector base on superconducting niobium nitride film sensitive to radiation in spectral range from millimeter waves up to visible light |
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Journal Article |
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Year |
1992 |
Publication |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
Abbreviated Journal |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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Volume |
5 |
Issue |
5 |
Pages |
955-960 |
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Keywords |
NbN HEB detectors |
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Abstract |
Fast-operating picosecond detector of electromagnetical radiation is developed on the basis of fine superconducting film of niobium nitride with high sensitivity within spectral range from millimetric waves up to visible light. Detector sensitive element represents structure covering narrow parallel strips with micron sizes included in the rupture of microstrip line. Detecting ability of the detector and time constant measured using amplitude-simulated radiation of reverse wave tubes and pulse radiation of picosecond gas and solid-body lasers, constitute D*≅1010 W-1·cm·Hz-1/2 and τ≤5 ps respectively, at 10 K temperature. The expected value of time constant of the detector at 10 K obtained via extrapolation of directly measured dependence that is, τ ∝ τ-1, constitutes 20 ps. Experimental data demonstrate that detection mechanism is linked with electron heating effect. |
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Russian |
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0131-5366 |
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1670 |
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Gershenzon, E. M.; Gol'tsman, G. N.; Karasik, B. S.; Lugovaya, G. Ya.; Serebryakova, N. A.; Chinkova, E. V. |
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Title |
Infrared radiation detectors on the base of electron heating in resistive state films from traditional superconducing materials |
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Journal Article |
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Year |
1992 |
Publication |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
Abbreviated Journal |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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Volume |
5 |
Issue |
6 |
Pages |
1129-1140 |
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Keywords |
IR HEB detectors |
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Abstract |
Characteristics of infrared radiation detectors based on electron heating in thin superconducting films transformed at T ≤ Tc to a resistive state by transport current and, if necessary, by magnetic field are investigated. A comparison is made of the characteristics of the detectors fabricated of different materials: aluminium, niobium, Mo0.5Re0.5. Some devices with different topology of the reception area are considered. Electron heating detectors are comparable by their sensitivity with superconducting bolometers, but differ in a high fast-response. |
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Russian |
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0131-5366 |
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Call Number |
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1673 |
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Author |
Gershenzon, E. M.; Gol'tsman, G. N.; Dzardanov, A. L.; Elant'ev, A. I.; Zorin, M. A.; Markin, A. G.; Semenov, A. D. |
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Title |
S-N switching of niobium and YBCO films: limit time and perspective of fast key element creation |
Type |
Journal Article |
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Year |
1992 |
Publication |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
Abbreviated Journal |
Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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Volume |
5 |
Issue |
12 |
Pages |
2386-2402 |
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Keywords |
YBCO HTS switches |
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A study was made on processes of switching of thin niobium film strips between superconducting and normal states under the effect of optical radiation pulse and voltage step. The results are described satisfactorily by the model of spatial homogeneous electron heating. It is shown that limiting switching times can be equal to several shares of nanosecond at 4.2 K. Preliminary results for YBa2Cu3O-7-x films are presented. Prospects and advantages of creation of ducting structures of narrow streps, are discussed. |
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0131-5366 |
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1674 |
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Budyanskij, M. Ya.; Sejdman, L. A.; Voronov, B. M.; Gubkina, T. O. |
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Increase of reproducibility in production of superconducting thin films of niobium nitride |
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1992 |
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Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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5 |
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10 |
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1950-1954 |
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NbN films |
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Technique to control the composition of gas medium in the reactive magnetron discharge and the composition of the deposited films of niobium nitride using electrical parameters of discharge only, in particular, by δU = Up – Uar value at contant stabilized discharge current is described. Technique to select optimal condition for deposition of niobium nitride films when the films have composition meeting chemical formula, is suggested. Thin films of niobium nitride with up to 7 nm thickness and with rather high temperature of transition into superconducting state Tk > 10 K) and with low width of transition (δ < 0.6 K), are obtained. It is determined, that substrate material and dielectric sublayer do not affect. Tk value, while difference in coefficients of thermal expansion of substrate and of film affects δTk value. |
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1675 |
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Varyukhin, S. V.; Zakharov, A. A.; Gershenzon, E. M.; Gol'tsman, G. N.; Ptitsina, N. G.; Chulkova, G. M. |
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Low energy excitation in La2CuO4 |
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1990 |
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Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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Sverkhprovodimost': Fizika, Khimiya, Tekhnika |
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3 |
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5 |
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832-837 |
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metal-dielectric-La2CuO4, monocrystals |
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Measurements of transmission and photoconductivity spectra in submillimeter wave length range as well as of capacity C and conductivity G in the region of acoustic frequencies of metal-dielectric-La2CuO4 system at low temperatures are performed using La2CuO4 monocrystals. Optical spectra posses a threshold character, a sharp decrease of transmission and photocoductivity signal occurs in the energy region hν>1.5 MeV. C(ω,T) and G(ω, T) dependences have a universal form typical of Debye type relaxation processes. Relaxation time dependence is of thermoactivated character τ(T)∼exp(ξ/T) with the gap value ξ≅2 meV. It is assumed that excitations with characteristic energy of ∼2 meV exist in La2CuO4. A possible nature of the detected low-energy excitations is discussed. |
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