| Records |
| Author |
Bandurin, D. A.; Svintsov, D.; Gayduchenko, I.; Xu, S. G.; Principi, A.; Moskotin, M.; Tretyakov, I.; Yagodkin, D.; Zhukov, S.; Taniguchi, T.; Watanabe, K.; Grigorieva, I. V.; Polini, M.; Goltsman, G. N.; Geim, A. K.; Fedorov, G. |
| Title |
Resonant terahertz detection using graphene plasmons |
Type |
Journal Article |
| Year |
2018 |
Publication |
Nat. Commun. |
Abbreviated Journal |
Nat. Commun. |
| Volume |
9 |
Issue |
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Pages |
5392 (1 to 8) |
| Keywords |
THz, graphene plasmons |
| Abstract |
Plasmons, collective oscillations of electron systems, can efficiently couple light and electric current, and thus can be used to create sub-wavelength photodetectors, radiation mixers, and on-chip spectrometers. Despite considerable effort, it has proven challenging to implement plasmonic devices operating at terahertz frequencies. The material capable to meet this challenge is graphene as it supports long-lived electrically tunable plasmons. Here we demonstrate plasmon-assisted resonant detection of terahertz radiation by antenna-coupled graphene transistors that act as both plasmonic Fabry-Perot cavities and rectifying elements. By varying the plasmon velocity using gate voltage, we tune our detectors between multiple resonant modes and exploit this functionality to measure plasmon wavelength and lifetime in bilayer graphene as well as to probe collective modes in its moire minibands. Our devices offer a convenient tool for further plasmonic research that is often exceedingly difficult under non-ambient conditions (e.g. cryogenic temperatures) and promise a viable route for various photonic applications. |
| Address |
Physics Department, Moscow State University of Education (MSPU), Moscow, Russian Federation, 119435. fedorov.ge@mipt.ru |
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2041-1723 |
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1148 |
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Baeva, E. M.; Titova, N. A.; Veyrat, L.; Sacépé, B.; Semenov, A. V.; Goltsman, G. N.; Kardakova, A. I.; Khrapai, V. S. |
| Title |
Thermal relaxation in metal films bottlenecked by diffuson lattice excitations of amorphous substrates |
Type |
Miscellaneous |
| Year |
2021 |
Publication |
arXiv |
Abbreviated Journal |
arXiv |
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| Keywords |
metal films, NbN, InOx, Au/Ni, thermal relaxation |
| Abstract |
Here we examine the role of the amorphous insulating substrate in the thermal relaxation in thin NbN, InOx, and Au/Ni films at temperatures above 5 K. The studied samples are made up of metal bridges on an amorphous insulating layer lying on or suspended above a crystalline substrate. Noise thermometry was used to measure the electron temperature Te of the films as a function of Joule power per unit of area P2D. In all samples, we observe the dependence P2D∝Tne with the exponent n≃2, which is inconsistent with both electron-phonon coupling and Kapitza thermal resistance. In suspended samples, the functional dependence of P2D(Te) on the length of the amorphous insulating layer is consistent with the linear T-dependence of the thermal conductivity, which is related to lattice excitations (diffusons) for the phonon mean free path smaller than the dominant phonon wavelength. Our findings are important for understanding the operation of devices embedded in amorphous dielectrics. |
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no |
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1163 |
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Titova, N. A.; Baeva, E. M.; Kardakova, A. I.; Goltsman, G. N. |
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Fabrication of NbN/SiNx:H/SiO2 membrane structures for study of heat conduction at low temperatures |
Type |
Conference Article |
| Year |
2020 |
Publication |
J. Phys.: Conf. Ser. |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
| Volume |
1695 |
Issue |
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Pages |
012190 |
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NbN films, insulating membrane |
| Abstract |
Here we report on the development of NbN/SiNx:H/SiO2-membrane structures for investigation of the thermal transport at low temperatures. Thin NbN films are known to be in the regime of a strong electron-phonon coupling, and one can assume that the phononic and electronic baths in the NbN are in local equilibrium. In such case, the cooling of the NbN-based devices strongly depends on acoustic matching to the substrate and substrate thermal characteristics. For the insulating membrane much thicker than the NbN film, our preliminary results demonstrate that the membrane serves as an additional channel for the thermal relaxation of the NbN sample. That implies a negligible role of thermal boundary resistance of the NbN-SiNx:H interface in comparison with the internal thermal resistance of the insulating membrane. |
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1742-6588 |
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no |
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1165 |
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Saveskul, N. A.; Titova, N. A.; Baeva, E. M.; Semenov, A. V.; Lubenchenko, A. V.; Saha, S.; Reddy, H.; Bogdanov, S. I.; Marinero, E. E.; Shalaev, V. M.; Boltasseva, A.; Khrapai, V. S.; Kardakova, A. I.; Goltsman, G. N. |
| Title |
Superconductivity behavior in epitaxial TiN films points to surface magnetic disorder |
Type |
Journal Article |
| Year |
2019 |
Publication |
Phys. Rev. Applied |
Abbreviated Journal |
Phys. Rev. Applied |
| Volume |
12 |
Issue |
5 |
Pages |
054001 |
| Keywords |
epitaxial TiN films |
| Abstract |
We analyze the evolution of the normal and superconducting properties of epitaxial TiN films, characterized by high Ioffe-Regel parameter values, as a function of the film thickness. As the film thickness decreases, we observe an increase of the residual resistivity, that becomes dominated by diffusive surface scattering for d≤20nm. At the same time, a substantial thickness-dependent reduction of the superconducting critical temperature is observed compared to the bulk TiN value. In such high-quality material films, this effect can be explained by a weak magnetic disorder residing in the surface layer with a characteristic magnetic defect density of approximately 1012cm−2. Our results suggest that surface magnetic disorder is generally present in oxidized TiN films. |
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2331-7019 |
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no |
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1166 |
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Kardakova, A.; Shishkin, A.; Semenov, A.; Goltsman, G. N.; Ryabchun, S.; Klapwijk, T. M.; Bousquet, J.; Eon, D.; Sacépé, B.; Klein, T.; Bustarret, E. |
| Title |
Relaxation of the resistive superconducting state in boron-doped diamond films |
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Journal Article |
| Year |
2016 |
Publication |
Phys. Rev. B |
Abbreviated Journal |
Phys. Rev. B |
| Volume |
93 |
Issue |
6 |
Pages |
064506 |
| Keywords |
boron-doped diamond films, resistive superconducting state, relaxation time |
| Abstract |
We report a study of the relaxation time of the restoration of the resistive superconducting state in single crystalline boron-doped diamond using amplitude-modulated absorption of (sub-)THz radiation (AMAR). The films grown on an insulating diamond substrate have a low carrier density of about 2.5×1021cm−3 and a critical temperature of about 2K. By changing the modulation frequency we find a high-frequency rolloff which we associate with the characteristic time of energy relaxation between the electron and the phonon systems or the relaxation time for nonequilibrium superconductivity. Our main result is that the electron-phonon scattering time varies clearly as T−2, over the accessible temperature range of 1.7 to 2.2 K. In addition, we find, upon approaching the critical temperature Tc, evidence for an increasing relaxation time on both sides of Tc. |
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2469-9950 |
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no |
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1167 |
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Tretyakov, I. V.; Finkel, M. I.; Ryabchun, S. A.; Kardakova, A. I.; Seliverstov, S. V.; Petrenko, D. V.; Goltsman, G. N. |
| Title |
Hot-electron bolometer mixers with in situ contacts |
Type |
Journal Article |
| Year |
2014 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
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56 |
Issue |
8-9 |
Pages |
591-598 |
| Keywords |
HEB mixers |
| Abstract |
We report on the latest achievements in the development of superconducting hot-electron bolometer (HEB) mixers for terahertz superheterodyne receivers. We consider application ranges of such receivers and requirements for the basic characteristics of the mixers. Main features of the mixers, such as noise temperature, gain bandwidth, noise bandwidth, and required local-oscillator power, have been improved significantly over the past few years due to intense research work, both in terms of the element fabrication quality and in terms of understanding of the physics of the processes occurring in the HEB mixers. Contacts between the superconducting bridge and the planar antenna play a key role in the mixer operation. Improvement of the quality of the contacts leads simultaneously to a decrease in the noise temperature and an increase in the gain bandwidth of a mixer. |
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0033-8443 |
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no |
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1170 |
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Elezov, M. S.; Semenov, A. V.; An, P. P.; Tarkhov, M. A.; Goltsman, G. N.; Kardakova, A. I.; Kazakov, A. Y. |
| Title |
Investigating the detection regimes of a superconducting single-photon detector |
Type |
Journal Article |
| Year |
2013 |
Publication |
J. Opt. Technol. |
Abbreviated Journal |
J. Opt. Technol. |
| Volume |
80 |
Issue |
7 |
Pages |
435 |
| Keywords |
SSPD, quantum efficiency |
| Abstract |
The detection regimes of a superconducting single-photon detector have been investigated. A technique is proposed for determining the regions in which “pure regimes” predominate. Based on experimental data, the dependences of the internal quantum efficiency on the bias current are determined in the one-, two-, and three-photon detection regimes. |
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1070-9762 |
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no |
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1172 |
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Venediktov, I. O.; Elezov, M. S.; Prokhodtsov, A. I.; Kovalyuk, V. V.; An, P. P.; Golikov, A. D.; Shcherbatenko, M. L.; Sych, D. V.; Goltsman, G. N. |
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Study of microheater’s phase modulation for on-chip Kennedy receiver |
Type |
Conference Article |
| Year |
2020 |
Publication |
J. Phys.: Conf. Ser. |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
| Volume |
1695 |
Issue |
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Pages |
012117 |
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Mach-Zehnder interferometers, MZI |
| Abstract |
In this work we describe phase modulators for several Mach-Zehnder interferometers (MZI) on silicon nitride platform for telecomm wavelength (1550 nm). We obtained current-voltage and phase-voltage curves for these modulators. MZI are needed for experimental realisation of various quantum receivers that can distinguish weak coherent states of light with extremely low error. Thermo-optical (TO) modulation is ensured by microheaters on one of the arms of MZI, which enables the change of the refractive index of the material with temperature. This approach allows to apply the necessary voltage to the golden microheaters to obtain the required phase change. For the on-chip microheaters we demonstrate the dependence of the phase shift on the voltage applied to our on-chip microheaters. |
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1742-6588 |
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no |
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1179 |
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Zvagelsky, R. D.; Chubich, D. A.; Kolymagin, D. A.; Korostylev, E. V.; Kovalyuk, V. V.; Prokhodtsov, A. I.; Tarasov, A. V.; Goltsman, G. N.; Vitukhnovsky, A. G. |
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Three-dimensional polymer wire bonds on a chip: morphology and functionality |
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Journal Article |
| Year |
2020 |
Publication |
J. Phys. D: Appl. Phys. |
Abbreviated Journal |
J. Phys. D: Appl. Phys. |
| Volume |
53 |
Issue |
35 |
Pages |
355102 |
| Keywords |
photonic wire bonds, PWB |
| Abstract |
Modern microchip-scale transceivers are capable of transmitting data at rates of the order of several terabits per second. In this regard, there is an urgent need to improve the interfaces connecting the chips and extend the bandpass of the interconnections. We use an approach combining silicon nitride nanophotonic circuits with 3D polymer waveguides fabricated by direct laser writing, which can be used as photonic interconnections or photonic wire bonds (PWB). These structures are designed, simulated, fabricated, and optimized for better light transmission at the telecommunication wavelength. An important part of this work is the study of the telecom signal transmission in a 3D polymer waveguide connecting two silicon nitride facing tapers. Two cases are considered: the tapers are one opposite the other or misaligned. Initially, the PWB shape was chosen to be Gaussian and then optimized: the top was circle-shaped and with the lower part still being Gaussian. Transmission losses were measured for both types of waveguides with different shapes. The idea of an optical multi-level crossing for photonic integrated circuits is also suggested as a solution to the problem of interconnections within a single chip. |
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0022-3727 |
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no |
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1181 |
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Bakhvalova, T.; Belkin, M. E.; Kovalyuk, V. V.; Prokhodtcov, A. I.; Goltsman, G. N.; Sigov, A. S. |
| Title |
Studying key principles for design and fabrication of silicon photonic-based beamforming networks |
Type |
Conference Article |
| Year |
2019 |
Publication |
PIERS-Spring |
Abbreviated Journal |
PIERS-Spring |
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Issue |
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Pages |
745-751 |
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silicon photonics, TriPleX platform |
| Abstract |
In the paper, we address key principles for computer-aided design and fabrication of silicon-photonics-based optical beamforming network selecting the optimal approach by simulation and experimental results. To clarify the consideration, the study is conducted on the example of a widely used binary switchable silicon-nitride optical beamforming network based on TriPleX platform. Comparison of simulation results and experimental studies of the prototype shows that the relative error due to technological imperfections does not exceed 3%. According to the estimation, such an error introduces insignificant distortion in the radiation pattern of the referred antenna array. |
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no |
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9017646 |
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1186 |
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Elezov, M. S.; Scherbatenko, M. L.; Sych, D. V.; Goltsman, G. N. |
| Title |
Active and passive phase stabilization for the all-fiber Michelson interferometer |
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Conference Article |
| Year |
2018 |
Publication |
J. Phys.: Conf. Ser. |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
| Volume |
1124 |
Issue |
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Pages |
051014 (1 to 5) |
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Michelson interferometer, phase stabilization |
| Abstract |
We put forward two methods for phase stabilization in the all-fiber Michelson interferometer. To perform passive phase stabilization, we use a heat bath for all fibers and electro-optical components, and put the interferometer in a hermetic case. To perform active phase stabilization, we monitor output power of the interferometer and develop an electronic feedback control. The phase stabilization methods enable stable interference pattern for several minutes, and can be helpful for the development of the optimal quantum receiver for coherent signals. |
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1742-6588 |
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1299 |
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Goltsman, G. N.; Shcherbatenko, M. L.; Lobanov, Y. V.; Kovalyuk, V. V.; Kahl, O.; Ferrari, S.; Korneev, A.; Pernice, W. H. P. |
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Superconducting nanowire single photon detector for coherent detection of weak optical signals |
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Abstract |
| Year |
2016 |
Publication |
LPHYS'16 |
Abbreviated Journal |
LPHYS'16 |
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Issue |
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1-2 |
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SSPD, SNSPD |
| Abstract |
Traditionally, photon detectors are operated in a direct detection mode counting incident photonswith a known quantum efficiency. This procedure allows one to detect weak sources of radiation but allthe information about its frequency is limited by the optical filtering/resonating structures used which arenot as precise as would be required for some practical applications. In this work we propose heterodynereceiver based on a photon counting mixer which would combine excellent sensitivity of a photon countingdetector and excellent spectral resolution given by the heterodyne technique. At present, Superconducting-Nanowire-Single-Photon-Detectors (SNSPDs) [1] are widely used in a variety of applications providing thebest possible combination of the sensitivity and speed. SNSPDs demonstrate lack of drawbacks like highdark count rate or autopulsing, which are common for traditional semiconductor-based photon detectors,such as avalanche photon diodes.In our study we have investigated SNSPD operated as a photon counting mixer. To fully understandits behavior in such a regime, we have utilized experimental setup based on a couple of distributedfeedback lasers irradiating at 1.5 micrometers, one of which is being the Local Oscillator (LO) and theother mimics the test signal [2]. The SNSPD was operated in the current mode and the bias currentwas slightly below of the critical current. Advantageously, we have found that LO power needed for anoptimal mixing is of the order of hundreds of femtowatts to a few picowatts, which is promising for manypractical applications, such as receiver matrices [3]. With use of the two lasers, one can observe thevoltage pulses produced by the detected photons, and the time distribution of the pulses reproduces thefrequency difference between the lasers, forming power response at the intermediate frequency which canbe captured by either an oscilloscope (an analysis of the pulse statistics is needed) or by an RF spectrumanalyzer. Photon-counting nature of the detector ensures quantum-limited sensitivity with respect to theoptical coupling achieved. In addition to the chip SNSPD with normal incidence coupling, we use thedetectors with a travelling wave geometry design [4]. In this case a NbN nanowire is placed on the topof a Si3N4 nanophotonic waveguide, thus increasing the efficient interaction length. For this reason it ispossible to achieve almost complete absorption of photons and reduce the detector footprint. This reducesthe noise of the device together with the expansion of the bandwidth. Integrated device scheme allowsus to measure the optical losses with high accuracy. Our approach is fully scalable and, along with alarge number of devices integrated on a single chip can be adapted to the mid and far IR ranges wherephoton-counting measurement may be beneficial as well [5].Acknowledgements: This work was supported in part by the Ministry of Education and Science of theRussian Federation, contract No. 14.B25.31.0007 and by RFBR grant No. 16-32-00465. |
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1220 |
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Zolotov, P. I.; Semenov, A. V.; Divochiy, A. V.; Goltsman, G. N.; Romanov, N. R.; Klapwijk, T. M. |
| Title |
Dependence of photon detection efficiency on normal-state sheet resistance in marginally superconducting films of NbN |
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Journal Article |
| Year |
2021 |
Publication |
IEEE Trans. Appl. Supercond. |
Abbreviated Journal |
IEEE Trans. Appl. Supercond. |
| Volume |
31 |
Issue |
5 |
Pages |
1-5 |
| Keywords |
NbN SSPD, SNSPD |
| Abstract |
We present an extensive set of data on nanowire-type superconducting single-photon detectors based on niobium-nitride (NbN) to establish the empirical correlation between performance and the normal-state resistance per square. We focus, in particular, on the bias current, compared to the expected depairing current, needed to achieve a near-unity detection efficiency for photon detection. The data are discussed within the context of a model in which the photon energy triggers the movement of vortices i.e. superconducting dissipation, followed by thermal runaway. Since the model is based on the non-equilibrium theory for conventional superconductors deviations may occur, because the efficient regime is found when NbN acts as a marginal superconductor in which long-range phase coherence is frustrated. |
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1051-8223 |
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no |
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1222 |
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| Author |
Baeva, E. M.; Sidorova, M. V.; Korneev, A. A.; Smirnov, K. V.; Divochy, A. V.; Morozov, P. V.; Zolotov, P. I.; Vakhtomin, Y. B.; Semenov, A. V.; Klapwijk, T. M.; Khrapai, V. S.; Goltsman, G. N. |
| Title |
Thermal properties of NbN single-photon detectors |
Type |
Journal Article |
| Year |
2018 |
Publication |
Phys. Rev. Applied |
Abbreviated Journal |
Phys. Rev. Applied |
| Volume |
10 |
Issue |
6 |
Pages |
064063 (1 to 8) |
| Keywords |
NbN SSPD, SNSPD |
| Abstract |
We investigate thermal properties of a NbN single-photon detector capable of unit internal detection efficiency. Using an independent calibration of the coupling losses, we determine the absolute optical power absorbed by the NbN film and, via resistive superconductor thermometry, the temperature dependence of the thermal resistance Z(T) of the NbN film. In principle, this approach permits simultaneous measurement of the electron-phonon and phonon-escape contributions to the energy relaxation, which in our case is ambiguous because of the similar temperature dependencies. We analyze Z(T) with a two-temperature model and impose an upper bound on the ratio of electron and phonon heat capacities in NbN, which is surprisingly close to a recent theoretical lower bound for the same quantity in similar devices. |
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| ISSN |
2331-7019 |
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no |
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Serial |
1226 |
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| Author |
Iomdina, E. N.; Seliverstov, S. V.; Teplyakova, K. O.; Jani, E. V.; Pozdniakova, V. V.; Polyakova, O. N.; Goltsman, G. N. |
| Title |
Terahertz scanning of the rabbit cornea with experimental UVB-induced damage: in vivo assessment of hydration and its verification |
Type |
Journal Article |
| Year |
2021 |
Publication |
J. Biomed. Opt. |
Abbreviated Journal |
J. Biomed. Opt. |
| Volume |
26 |
Issue |
4 |
Pages |
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| Keywords |
medicine; scheimpflug imaging; UVB; confocal microscopy; cornea; optical coherent tomography; rabbit eyes; terahertz radiation |
| Abstract |
SIGNIFICANCE: Water content plays a vital role in the normally functioning visual system; even a minor disruption in the water balance may be harmful. Today, no direct method exists for corneal hydration assessment, while it could be instrumental in early diagnosis and control of a variety of eye diseases. The use of terahertz (THz) radiation, which is highly sensitive to water content, appears to be very promising. AIM: To find out how THz scanning parameters of corneal tissue measured by an experimental setup, specially developed for in vivo contactless estimations of corneal reflectivity coefficient (RC), are related to pathological changes in the cornea caused by B-band ultraviolet (UVB) exposure. APPROACH: The setup was tested on rabbit eyes in vivo. Prior to the course of UVB irradiation and 1, 5, and 30 days after it, a series of examinations of the corneal state was made. At the same time points, corneal hydration was assessed by measuring RC. RESULTS: The obtained data confirmed the negative impact of UVB irradiation course on the intensity of tear production and on the corneal thickness and optical parameters. A significant (1.8 times) increase in RC on the 5th day after the irradiation course, followed by a slight decrease on the 30th day after it was revealed. The RC increase measured 5 days after the UVB irradiation course generally corresponded to the increase (by a factor of 1.3) of tear production. RC increase occurred with the corneal edema, which was manifested by corneal thickening (by 18.2% in the middle area and 17.6% in corneal periphery) and an increased volume of corneal tissue (by 17.6%). CONCLUSIONS: Our results demonstrate that the proposed approach can be used for in vivo contactless estimation of the reflectivity of rabbit cornea in the THz range and, thereby, of cornea hydration. |
| Address |
National Research University Higher School of Economics, Moscow Institute of Electronics and Mathema, Russia |
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English |
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1083-3668 |
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PMID:33834684; PMCID:PMC8027227 |
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no |
| Call Number |
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Serial |
1258 |
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