| Records |
| Author |
Zolotov, P.; Divochiy, A.; Vakhtomin, Y.; Moshkova, M.; Morozov, P.; Seleznev, V.; Smirnov, K. |
| Title |
Photon-number-resolving SSPDs with system detection efficiency over 50% at telecom range |
Type |
Conference Article |
Year  |
2018 |
Publication |
Proc. AIP Conf. |
Abbreviated Journal |
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| Volume |
1936 |
Issue |
1 |
Pages |
020019 |
| Keywords |
NbN PNR SSPD, SNSPD |
| Abstract |
We used technology of making high-efficiency superconducting single-photon detectors as a basis for improvement of photon-number-resolving devices. By adding optical cavity and using an improved NbN superconducting film, we enhanced previously reported system detection efficiency at telecom range for such detectors. Our results show that implementation of optical cavity helps to develop four-section device with quantum efficiency over 50% at 1.55 µm. Performed experimental studies of detecting multi-photon optical pulses showed irregularities over defining multi-photon through single-photon quantum efficiency. |
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doi:10.1063/1.5025457 |
Serial |
1231 |
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| Author |
Smirnov, K.; Divochiy, A.; Vakhtomin, Y.; Morozov, P.; Zolotov, P.; Antipov, A.; Seleznev, V. |
| Title |
NbN single-photon detectors with saturated dependence of quantum efficiency |
Type |
Journal Article |
| Year |
2018 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
| Volume |
31 |
Issue |
3 |
Pages |
035011 (1 to 8) |
| Keywords |
NbN SSPD, SNSPD |
| 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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Edition |
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| ISSN |
0953-2048 |
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no |
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1232 |
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Korneeva, Y. P.; Vodolazov, D. Y.; Semenov, A. V.; Florya, I. N.; Simonov, N.; Baeva, E.; Korneev, A. A.; Goltsman, G. N.; Klapwijk, T. M. |
| Title |
Optical single-photon detection in micrometer-scale NbN bridges |
Type |
Journal Article |
| Year |
2018 |
Publication |
Phys. Rev. Applied |
Abbreviated Journal |
Phys. Rev. Applied |
| Volume |
9 |
Issue |
6 |
Pages |
064037 (1 to 13) |
| Keywords |
NbN SSPD, SNSPD |
| Abstract |
We demonstrate experimentally that single-photon detection can be achieved in micrometer-wide NbN bridges, with widths ranging from 0.53 to 5.15 μm and for photon wavelengths of 408 to 1550 nm. The microbridges are biased with a dc current close to the experimental critical current, which is estimated to be about 50% of the theoretically expected depairing current. These results offer an alternative to the standard superconducting single-photon detectors, based on nanometer-scale nanowires implemented in a long meandering structure. The results are consistent with improved theoretical modeling based on the theory of nonequilibrium superconductivity, including the vortex-assisted mechanism of initial dissipation. |
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| ISSN |
2331-7019 |
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no |
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Serial |
1303 |
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Tretyakov, I. V.; Anfertyev, V. A.; Revin, L. S.; Kaurova, N. S.; Voronov, B. M.; Vaks, V. L.; Goltsman, G. N. |
| Title |
Sensitivity and resolution of a heterodyne receiver based on the NbN HEB mixer with a quantum-cascade laser as a local oscillator |
Type |
Journal Article |
| Year |
2018 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
| Volume |
60 |
Issue |
12 |
Pages |
988-992 |
| Keywords |
NbN HEB mixer |
| Abstract |
We present the results of experimental studies of the basic characteristics and operation features of a terahertz heterodyne detector based on the superconducting NbN HEB mixer and a quantum cascade laser as a local oscillator operating at a frequency of 2.02 THz. The measured noise temperature of such a mixer amounted to 1500 K. The spectral resolution of the detector is determined by the width of the local-oscillator spectral line whose measured value does not exceed 1 MHz. The quantum-cascade laser could be linearly tuned with respect to frequency with the coefficient 7.2 MHz/mA within the limits of the current oscillation bandwidth. |
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Edition |
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| ISSN |
0033-8443 |
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no |
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Serial |
1307 |
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| Author |
Baeva, E.; Sidorova, M.; Korneev, A.; Goltsman, G. |
| Title |
Precise measurement of the thermal conductivity of superconductor |
Type |
Conference Article |
| Year |
2018 |
Publication |
Proc. AIP Conf. |
Abbreviated Journal |
Proc. AIP Conf. |
| Volume |
1936 |
Issue |
1 |
Pages |
020003 (1 to 4) |
| Keywords |
NbN SSPD, SNSPD |
| Abstract |
Measuring the thermal properties such as the heat capacity provide information about intrinsic mechanisms operated inside. In general, the ratio between electron and phonon specific heat Ce/Cp shows how the absorbed energy shared between electron and phonon subsystems. In this work we make estimations for amplitude-modulated absorption of THz radiation technique for investigation of the ratio Ce/Cp in superconducting Niobium Nitride (NbN) at T = Tc. Our results indicates that experimentally the frequency of modulation has to be extra large to extract the quantity. We perform a new technique allowed to work at low frequency with accurately measurement of absorbed power. |
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no |
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doi:10.1063/1.5025441 |
Serial |
1311 |
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| Author |
Tretyakov, Ivan; Kaurova, N.; Voronov, B. M.; Goltsman, G. N. |
| Title |
About effect of the temperature operating conditions on the noise temperature and noise bandwidth of the terahertz range NbN hot-electron bolometers |
Type |
Abstract |
| Year |
2018 |
Publication |
Proc. 29th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 29th Int. Symp. Space Terahertz Technol. |
| Volume |
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Issue |
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Pages |
113 |
| Keywords |
NbN HEB mixer |
| Abstract |
Results of an experimental study of the noise temperature (Tn) and noise bandwidth (NBW) of the superconductor NbN hot-electron bolometer (HEB) mixer as a function of its temperature (Tb) and NbN bridge length are presented. It was determined that the NBW of the mixer is significantly wider at temperatures close to the critical ones (Tc) than are values measured at 4.2 K. The NBW of the mixer measured at the heterodyne frequency of 2.5 THz at temperature Tb close to Tc was ~13 GHz, as compared with 6 GHz at Tb = 4.2 K. This experiment clearly demonstrates the limitation of the thermal flow from the NbN bridge at Tb ≪ Tc for mixers manufactured by the in situ technique. This limitation is close in its nature to the Andreev reflection on the superconductor/metal boundary. In this case, the noise temperature of the studied mixer increased from 1100 to 3800 K. |
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Approved |
no |
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Serial |
1313 |
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| Author |
Tretyakov, I.; Kaurova, N.; Raybchun, S.; Goltsman, G. N.; Silaev, A. A. |
| Title |
Technology for NbN HEB based multipixel matrix of THz range |
Type |
Conference Article |
| Year |
2018 |
Publication |
EPJ Web Conf. |
Abbreviated Journal |
EPJ Web Conf. |
| Volume |
195 |
Issue |
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Pages |
05011 |
| Keywords |
NbN HEB |
| Abstract |
The influence of homogeneity disorder degree of the thin superconducting NbN film across of Si wafer on characteristics of the Hot Electron Bolometers (HEB) has been investigated. Our experiments have been carried out near the superconducting transition and far below it. The high homogeneity disorder degree of the NbN film has been achieved by preparing the Si substrate surface. The fabricated HEBs all have almost identical R (T) characteristics with a dispersion of Tc and the normal resistance R300 of not more than 0.15K and 2 Ω, respectively. The quality of the devises allows us to demonstrate clearly the influence of non-equilibrium processes in the S’SS’ system on the device performance. Our fabrication technology also allows creating multiplex heterodyne and direct detector matrices based the HEB devices. |
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Edition |
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| ISSN |
2100-014X |
ISBN |
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Approved |
no |
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Serial |
1318 |
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| Author |
Kuznetsov, K. A.; Kornienko, V. V.; Vakhtomin, Y. B.; Pentin, I. V.; Smirnov, K. V.; Kitaeva, G. K. |
| Title |
Generation and detection of optical-terahertz biphotons via spontaneous parametric downconversion |
Type |
Conference Article |
| Year |
2018 |
Publication |
Proc. ICLO |
Abbreviated Journal |
Proc. ICLO |
| Volume |
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Issue |
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Pages |
303 |
| Keywords |
NbN HEB applications |
| Abstract |
We study spontaneous parametric downconversion (SPDC) in the strongly non-degenerate regime when the idler wave hits the terahertz range. By using the hot-electron bolometer, for the first time the SPDC-generated idler-wave photons were directly detected in the terahertz frequency range. Spectrum of corresponding signal photons was measured using standard technique by the CCD camera. Possible applications of correlated optical-terahertz biphotons are discussed. |
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Conference |
International Conference Laser Optics |
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Approved |
no |
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Serial |
1806 |
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| Author |
Lobanov, Y. V.; Vakhtomin, Y. B.; Pentin, I. V.; Khabibullin, R. A.; Shchavruk, N. V.; Smirnov, K. V.; Silaev, A. A. |
| Title |
Characterization of the THz quantum cascade laser using fast superconducting hot electron bolometer |
Type |
Journal Article |
| Year |
2018 |
Publication |
EPJ Web Conf. |
Abbreviated Journal |
EPJ Web Conf. |
| Volume |
195 |
Issue |
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Pages |
04004 (1 to 2) |
| Keywords |
NbN HEB, QCL |
| Abstract |
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2100-014X |
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3rd International Conference “Terahertz and Microwave Radiation: Generation, Detection and Applications” (TERA-2018) |
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Approved |
no |
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Serial |
1808 |
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| Author |
Sidorova, M.; Semenov, A.; Hübers, H.-W.; Kuzmin, A.; Doerner, S.; Ilin, K.; Siegel, M.; Charaev, I.; Vodolazov, D. |
| Title |
Timing jitter in photon detection by straight superconducting nanowires: Effect of magnetic field and photon flux |
Type |
Journal Article |
| Year |
2018 |
Publication |
Phys. Rev. B |
Abbreviated Journal |
Phys. Rev. B |
| Volume |
98 |
Issue |
13 |
Pages |
134504 (1 to 14) |
| Keywords |
SNSPD, NbN namowires |
| Abstract |
We studied the effects of the external magnetic field and photon flux on timing jitter in photon detection by straight superconducting NbN nanowires. At two wavelengths 800 and 1560 nm, statistical distribution in the appearance times of photon counts exhibits Gaussian shape at small times and an exponential tail at large times. The characteristic exponential time is larger for photons with smaller energy and increases with external magnetic field while variations in the Gaussian part of the distribution are less pronounced. Increasing photon flux drives the nanowire from the discrete quantum detection regime to the uniform bolometric regime that averages out fluctuations of the total number of nonequilibrium electrons created by the photon and drastically reduces jitter. The difference between standard deviations of Gaussian parts of distributions for these two regimes provides the measure for the strength of electron-number fluctuations; it increases with the photon energy. We show that the two-dimensional hot-spot detection model explains qualitatively the effect of magnetic field. |
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Series Issue |
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Edition |
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| ISSN |
2469-9950 |
ISBN |
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Medium |
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Conference |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1842 |
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| Author |
Moshkova, M.; Divochiy, A.; Morozov, P.; Vakhtomin, Y.; Antipov, A.; Zolotov, P.; Seleznev, V.; Ahmetov, M.; Smirnov, K. |
| Title |
High-performance superconducting photon-number-resolving detectors with 86% system efficiency at telecom range |
Type |
Journal Article |
| Year |
2019 |
Publication |
J. Opt. Soc. Am. B |
Abbreviated Journal |
J. Opt. Soc. Am. B |
| Volume |
36 |
Issue |
3 |
Pages |
B20 |
| Keywords |
NbN PNR SSPD, SNSPD |
| Abstract |
The use of improved fabrication technology, highly disordered NbN thin films, and intertwined section topology makes it possible to create high-performance photon-number-resolving superconducting single-photon detectors (PNR SSPDs) that are comparable to conventional single-element SSPDs at the telecom range. The developed four-section PNR SSPD has simultaneously an 86±3% system detection efficiency, 35 cps dark count rate, ∼2 ns dead time, and maximum 90 ps jitter. An investigation of the PNR SSPD’s detection efficiency for multiphoton events shows good uniformity across sections. As a result, such a PNR SSPD is a good candidate for retrieving the photon statistics for light sources and quantum key distribution systems. |
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Series Issue |
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Edition |
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| ISSN |
0740-3224 |
ISBN |
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Approved |
no |
| Call Number |
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Serial |
1225 |
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| Author |
Rasulova, G. K.; Pentin, I. V.; Goltsman, G. N. |
| Title |
Terahertz emission from a weakly-coupled GaAs/AlGaAs superlattice biased into three different modes of current self-oscillations |
Type |
Journal Article |
| Year |
2019 |
Publication |
AIP Advances |
Abbreviated Journal |
AIP Advances |
| Volume |
9 |
Issue |
10 |
Pages |
105220 |
| Keywords |
GaAs/AlGaAs superlattice, SL, NbN HEB |
| Abstract |
Radio-frequency modulated terahertz (THz) emission power from weakly-coupled GaAs/AlGaAs superlattice (SL) has been increased by parallel connection of several SL mesas. Each SL mesa is a self-oscillator with its own oscillation frequency and mode. In coupled non-identical SL mesas biased at different voltages within the hysteresis loop the chaotic, quasiperiodic and frequency-locked modes of self-oscillations of current arise. THz emission was detected when three connected in parallel SL mesas were biased into the frequency-locked and quasiperiodic modes of self-oscillations of current, while in the chaotic mode of those it falls to the noise level. |
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Edition |
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| ISSN |
2158-3226 |
ISBN |
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Approved |
no |
| Call Number |
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Serial |
1274 |
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| Author |
Antipov, S.; Trifonov, A.; Krause, S.; Meledin, D.; Kaurova, N.; Rudzinski, M.; Desmaris, V.; Belitsky, V.; Goltsman, G. |
| Title |
Improved bandwidth of a 2 THz hot-electron bolometer heterodyne mixer fabricated on sapphire with a GaN buffer layer |
Type |
Journal Article |
| Year |
2019 |
Publication |
Supercond. Sci. Technol. |
Abbreviated Journal |
Supercond. Sci. Technol. |
| Volume |
32 |
Issue |
7 |
Pages |
075003 |
| Keywords |
NbN HEB mixer, GaN buffer layer, sapphire substrate |
| 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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no |
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Antipov_2019 |
Serial |
1277 |
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| Author |
Ren, Y.; Zhang, D. X.; Zhou, K. M.; Miao, W.; Zhang, W.; Shi, S. C.; Seleznev, V.; Pentin, I.; Vakhtomin, Y.; Smirnov, K. |
| Title |
10.6 μm heterodyne receiver based on a superconducting hot-electron bolometer mixer and a quantum cascade laser |
Type |
Journal Article |
| Year |
2019 |
Publication |
AIP Advances |
Abbreviated Journal |
AIP Advances |
| Volume |
9 |
Issue |
7 |
Pages |
075307 |
| Keywords |
NbN HEB mixers, QCL, IR |
| Abstract |
We report on the development of a heterodyne receiver at mid-infrared wavelength for high-resolution spectroscopy applications. The receiver employs a superconducting NbN hot electron bolometer as a mixer and a room temperature distributed feedback quantum cascade laser operating at 10.6 μm (28.2 THz) as a local oscillator. The stabilization of the heterodyne receiver has been achieved using a feedback loop controlling the output power of the laser. Improved Allan variance times as well as a double sideband receiver noise temperature of 5000 K and a noise bandwidth of 2.8 GHz of the receiver system are demonstrated.
The work is supported in part by the National Key R&D Program of China under Grant 2018YFA0404701, by the CAS program under Grant QYZDJ-SSW-SLH043 and GJJSTD20180003, by the National Natural Science Foundation of China (NSFC) under Grant 11773083, by the “Hundred Talents Program” of the “Pioneer Initiative”, and in part by the CAS Key Lab for Radio Astronomy. |
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2158-3226 |
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Approved |
no |
| Call Number |
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Serial |
1293 |
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| Author |
Baeva, E. M.; Titova, N. A.; Kardakova, A. I.; Piatrusha, S. U.; Khrapai, V. S. |
| Title |
Universal bottleneck for thermal relaxation in disordered metallic films |
Type |
Journal Article |
| Year |
2020 |
Publication |
JETP Lett. |
Abbreviated Journal |
Jetp Lett. |
| Volume |
111 |
Issue |
2 |
Pages |
104-108 |
| Keywords |
NbN disordered metallic films, thermal relaxation |
| Abstract |
We study the heat relaxation in current biased metallic films in the regime of strong electron–phonon coupling. A thermal gradient in the direction normal to the film is predicted, with a spatial temperature profile determined by the temperature-dependent heat conduction. In the case of strong phonon scattering, the heat conduction occurs predominantly via the electronic system and the profile is parabolic. This regime leads to the linear dependence of the noise temperature as a function of bias voltage, in spite of the fact that all the dimensions of the film are large compared to the electron–phonon relaxation length. This is in stark contrast to the conventional scenario of relaxation limited by the electron–phonon scattering rate. A preliminary experimental study of a 200-nm-thick NbN film indicates the relevance of our model for materials used in superconducting nanowire single-photon detectors. |
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0021-3640 |
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1164 |
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