| Records |
| Author |
Dube, I.; Jiménez, D.; Fedorov, G.; Boyd, A.; Gayduchenko, I.; Paranjape, M.; Barbara, P. |
| Title |
Understanding the electrical response and sensing mechanism of carbon-nanotube-based gas sensors |
Type |
Journal Article |
| Year |
2015 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
87 |
Issue |
|
Pages |
330-337 |
| Keywords |
carbon nanotubes, CNT detectors, field effect transistors, FET |
| Abstract |
Gas sensors based on carbon nanotube field effect transistors (CNFETs) have outstanding sensitivity compared to existing technologies. However, the lack of understanding of the sensing mechanism has greatly hindered progress on calibration standards and customization of these nano-sensors. Calibration requires identifying fundamental transistor parameters and establishing how they vary in the presence of a gas. This work focuses on modeling the electrical response of CNTFETs in the presence of oxidizing (NO2) and reducing (NH3) gases and determining how the transistor characteristics are affected by gas-induced changes of contact properties, such as the Schottky barrier height and width, and by the doping level of the nanotube. From the theoretical fits of the experimental transfer characteristics at different concentrations of NO2 and NH3, we find that the CNTFET response can be modeled by introducing changes in the Schottky barrier height. These changes are directly related to the changes in the metal work function of the electrodes that we determine experimentally, independently, with a Kelvin probe. Our analysis yields a direct correlation between the ON – current and the changes in the electrode metal work function. Doping due to molecules adsorbed at the carbon-nanotube/metal interface also affects the transfer characteristics. |
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Series Issue |
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Edition |
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| ISSN |
0008-6223 |
ISBN |
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no |
| Call Number |
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Serial |
1778 |
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| Author |
Karasik, B.S.; Milostnaya, I.I.; Zorin, M.A.; Elantev, A.I.; Gol'tsman, G.N.; Gershenzon, E.M. |
| Title |
Subnanosecond S-N and N-S switching of YBCO film induced by current pulse |
Type |
Journal Article |
| Year |
1994 |
Publication |
Phys. C: Supercond. |
Abbreviated Journal |
Phys. C: Supercond. |
| Volume |
235-240 |
Issue |
|
Pages |
1981-1982 |
| Keywords |
YBCO HTS switches |
| Abstract |
A transition of YBCO bridge 60 nm thick from superconducting to normal state induced by an abrupt current step has been studied. A subnanosecond stage has been observed during both S-N and N-S transition. The data obtained can be explained by hot-electron phenomena. On the basis of experimental results a prediction of picosecond switch performance has been made. |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0921-4534 |
ISBN |
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Medium |
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Conference |
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Approved |
no |
| Call Number |
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Serial |
1633 |
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| Author |
Gol'tsman, G. N.; Kouminov, P.; Goghidze, I.; Gershenzon, E. M. |
| Title |
Nonequilibrium kinetic inductive response of YBaCuO thin films to low-power laser pulses |
Type |
Journal Article |
| Year |
1994 |
Publication |
Phys. C: Supercond. |
Abbreviated Journal |
Phys. C: Supercond. |
| Volume |
235-240 |
Issue |
|
Pages |
1979-1980 |
| Keywords |
YBCO HTS KID |
| Abstract |
Transient non-equilibrium kinetic inductive voltage response of YBaCuO thin films to 20 ps pulses of YAG:Nd laser radiation with 0.63 μm and 1.5 μm wavelength has been revealed. By increasing the sensitivity of 100 ps resolution time registration system and diminishing light intensity (fluence 0.1-1 μJ2/cm2) and transport current (density j≤105 A/cm2) we observed a perculiar bipolar signal form with nearly equal amplitudes of each sign. The integration of the kinetic inductive response over time gives the result which is qualitatively of the same form as the response in the resistive and normal states: nonequilibrium picosecond scale component followed by bolometric nanosecond. Nonequilibrium response is interpreted as suppression of order parameter by excess of quasiparticles followed by a change in resistance in the resistive state and kinetic inductance in superconductive state. |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0921-4534 |
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 |
1634 |
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| Author |
Gershenzon, E. M.; Gol'tsman, G. N.; Gogidze, I. G.; Semenov, A. D.; Sergeev, A. V. |
| Title |
Processes of electron-phonon interaction in thin YBaCuO films |
Type |
Journal Article |
| Year |
1991 |
Publication |
Phys. C: Supercond. |
Abbreviated Journal |
Phys. C: Supercond. |
| Volume |
185-189 |
Issue |
|
Pages |
1371-1372 |
| Keywords |
YBCO HTS detectors |
| Abstract |
The ultrafast voltage response of YBaCuO films to laser radiation is studied and compared with previously investigated quasiparicles response to radiation of submillimeter wavelength range. Voltage shift under the visible light radiation has two components. Picosecond response realized as suppression superconductivity by nonequilibrium excess quasiparticles, response time is determined by quasiparticles recombination rate. Nanosecond response is probably due to bolometric effect. |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0921-4534 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1676 |
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| Author |
Gousev, Y. P.; Semenov, A. D.; Gol'tsman, G. N.; Sergeev, A. V.; Gershenzon, E. M. |
| Title |
Electron-phonon interaction in disordered NbN films |
Type |
Journal Article |
| Year |
1994 |
Publication |
Phys. B Condens. Mat. |
Abbreviated Journal |
Phys. B Condens. Mat. |
| Volume |
194-196 |
Issue |
|
Pages |
1355-1356 |
| Keywords |
NbN films |
| Abstract |
Electron-phonon interaction time has been investigated in disordered films of NbN. A temperatures below 5.5 K tau_eph ~ T -1"6 which is attributed to the renormalisation of phonon spectrum in thin films. |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0921-4526 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1649 |
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| Author |
Gershenzon, E. M.; Gol'tsman, G. N.; Potapov, V. D.; Sergeev, A. V. |
| Title |
Restriction of microwave enhancement of superconductivity in impure superconductors due to electron-electron interaction |
Type |
Journal Article |
| Year |
1991 |
Publication |
Phys. B Condens. Mat. |
Abbreviated Journal |
Phys. B Condens. Mat. |
| Volume |
169 |
Issue |
1-4 |
Pages |
629-630 |
| Keywords |
impure superconductors |
| Abstract |
Transition from microwave enhancement of supercurrent to superconductivity suppression is investigated in impure superconductors. It is demonstrated that frequency range of enhancement effect narrows with the decrease of electron mean free path, ℓ, and at ℓ⩽1nm electron heating is observed in the whole frequency range. Dependences of frequency boundaries on ℓ are explained by taking into account strong electron-electron interaction in impure metals. |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0921-4526 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1682 |
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| Author |
Verevkin, A. A.; Ptitsina, N. G.; Chulcova, G. M.; Gol'tsman, G. N.; Gershenzon, E. M.; Yngvesson, K. S. |
| Title |
Direct measurements of energy relaxation time of electrons in AlGaAs/GaAs heterostructures under quasi-equilibrium conditions |
Type |
Journal Article |
| Year |
1996 |
Publication |
Surface Science |
Abbreviated Journal |
Surface Science |
| Volume |
361-362 |
Issue |
|
Pages |
569-573 |
| Keywords |
2DEG, AlGaAs/GaAs heterostructures |
| Abstract |
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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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0039-6028 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1609 |
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| Author |
Bespalov, A.V.; Gol'tsman, G.N.; Semenov, A.D.; Renk, K.F. |
| Title |
Determination of the far-infrared emission characteristic of a cyclotron p-germanium laser by use of a superconducting Nb detector |
Type |
Journal Article |
| Year |
1991 |
Publication |
Solid State Communications |
Abbreviated Journal |
Solid State Communications |
| Volume |
80 |
Issue |
7 |
Pages |
503-506 |
| Keywords |
Nb detector, applications |
| Abstract |
We studied the far-infrared emission characteristics of a cyclotron p-germanium laser using a broad-band superconducting Nb film detector. For magnetic fields between ∼25 kOe and ∼50 kOe, emission in a frequency range from ∼50 cm-1 to ∼100 cm-1 with maximum intensity around 90 cm-1 was obtained. We determined, for fixed magnetic fields, electric field dependences of the emission intensity taking into account that the total electric field is a sum of the applied and the Hall electric field. An analysis of the emission intensity characteristic gives evidence that transitions between the two lowest Landau levels of light holes are responsible for the laser action. |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0038-1098 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1677 |
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| Author |
Gershenzon, E. M.; Gol'tsman, G. N.; Semenov, A. D.; Sergeev, A. V. |
| Title |
Mechanism of picosecond response of granular YBaCuO films to electromagnetic radiation |
Type |
Journal Article |
| Year |
1990 |
Publication |
Solid State Communications |
Abbreviated Journal |
Solid State Communications |
| Volume |
76 |
Issue |
4 |
Pages |
493-497 |
| Keywords |
YBCO HTS detectors |
| Abstract |
The ultrafast mechanisms of radiation detection in granular YBaCuO films are studied in the wide wavelength range from millimeter to near infrared. With the rise of radiation frequency the Josephson detection at the grain boundary weak links is replaced by electron heating into the grains. This change occurs in the submillimeter wavelength range. Electron-phonon relaxation time τeph is determined by direct measurements and analyses quasistationary electron heating. Temperature dependence of τeph at T ≤ 40 K was found to be τeph ∼ T−1. The results show that detectors with the response time of few picoseconds at nitrogen temperature are attainable. |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0038-1098 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1685 |
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| Author |
Gershenzon, E. M.; Gol'tsman, G. N.; Potapov, V. D.; Sergeev, A. V. |
| Title |
Restriction of microwave enhancement of superconductivity in impure superconductors due to electron-electron interaction |
Type |
Journal Article |
| Year |
1990 |
Publication |
Solid State Communications |
Abbreviated Journal |
Solid State Communications |
| Volume |
75 |
Issue |
8 |
Pages |
639-641 |
| Keywords |
impure superconductors |
| Abstract |
Transition from microwave enhancement of supercurrent to superconductivity suppression is investigated in impure superconductors. It is demonstrated that the frequency range of the enhancement effect narrows with the decrease of the electron mean free path, l, and at l ⩽ 1 nm electron heating is observed in the whole frequency range. Dependences of frequency boundaries on l are explained by taking into account strong electron-electron interaction in impure metals. |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0038-1098 |
ISBN |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1687 |
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| Author |
Gershenzon, E. M.; Gershenzon, M. E.; Gol'tsman, G. N.; Semyonov, A. D.; Sergeev, A. V. |
| Title |
Heating of electrons in superconductor in the resistive state due to electromagnetic radiation |
Type |
Journal Article |
| Year |
1984 |
Publication |
Solid State Communications |
Abbreviated Journal |
Solid State Communications |
| Volume |
50 |
Issue |
3 |
Pages |
207-212 |
| Keywords |
Nb HEB |
| Abstract |
The effect of heating electrons with respect to phonons in a thin superconducting film driven into the resistive state by the current and the external magnetic field has been observed and investigated. This effect caused by the electromagnetic radiation is manifested in the increased resistance of the film and is not selective over the frequency range from 1010 to 1015 Hz. That the effect is frequency independent under the conditions of strong electron scattering caused by static defects is explained by the decisive role of electron -electron collisions in forming the distribution function. The characteristic time of resistance change, obtained experimentally, corresponds to the relaxation time of the order parameter near the superconducting transition and to the relaxation time of the nonelastic electron-phonon interaction at lower temperatures and in lower magnetic fields. |
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Series Issue |
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Edition |
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| ISSN |
0038-1098 |
ISBN |
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Approved |
no |
| Call Number |
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Serial |
1709 |
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| Author |
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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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0033-8443 |
ISBN |
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| Notes |
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Approved |
no |
| Call Number |
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Serial |
1307 |
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| Author |
Seliverstov, S. V.; Anfertyev, V. A.; Tretyakov, I. V.; Ozheredov, I. A.; Solyankin, P. M.; Revin, L. S.; Vaks, V. L.; Rusova, A. A.; Goltsman, G. N.; Shkurinov, A. P. |
| Title |
Terahertz heterodyne receiver with an electron-heating mixer and a heterodyne based on the quantum-cascade laser |
Type |
Journal Article |
| Year |
2017 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
| Volume |
60 |
Issue |
7 |
Pages |
518-524 |
| Keywords |
NbN HEB mixer, QCL |
| Abstract |
We study characteristics of the laboratory prototype of a terahertz heterodyne receiver with an electron-heating mixer and a heterodyne based on the quantum-cascade laser. The results obtained demonstrate the possibility to use this receiver as a basis for creation of a high-sensitivity terahertz spectrometer, which can be used in many basic and practical applications. A significant advantage of this receiver will be the possibility of placing the mixer and heterodyne in the same cryostat, which will reduce the device dimensions considerably. The obtained experimental results are analyzed, and methods of optimizing the parameters of the receiver are proposed. |
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Series Issue |
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Edition |
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| ISSN |
0033-8443 |
ISBN |
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Approved |
no |
| Call Number |
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Serial |
1322 |
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| Author |
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. |
| Volume |
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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Series Issue |
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Edition |
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| ISSN |
0033-8443 |
ISBN |
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Approved |
no |
| Call Number |
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Serial |
1170 |
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| Author |
Smirnov, A. V.; Baryshev, A. M.; de Bernardis, P.; Vdovin, V. F.; Gol'tsman, G. N.; Kardashev, N. S.; Kuz'min, L. S.; Koshelets, V. P.; Vystavkin, A. N.; Lobanov, Yu. V.; Ryabchun, S. A.; Finkel, M. I.; Khokhlov, D. R. |
| Title |
The current stage of development of the receiving complex of the millimetron space observatory |
Type |
Journal Article |
| Year |
2012 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
| Volume |
54 |
Issue |
8 |
Pages |
557-568 |
| Keywords |
Millimetron space observatory, HEB applications |
| Abstract |
We present an overview of the state of the onboard receiving complex of the Millimetron space observatory in the development phase of its preliminary design. The basic parameters of the onboard equipment planned to create and required for astrophysical observations are considered. A review of coherent and incoherent detectors, which are central to each receiver of the observatory, is given. Their characteristics and limiting parameters feasible at the present level of technology are reported. |
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Approved |
no |
| Call Number |
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Serial |
1079 |
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