|   | 
Details
   web
Records
Author (up) Semenov, A. D.; Gol'tsman, G. N.
Title Non-thermal response of a diffusion-cooled hot-electron bolometer Type Journal Article
Year 1999 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 9 Issue 2 Pages 4491-4494
Keywords HEB mixers, non-thermal
Abstract We present an analysis of a diffusion-cooled hot-electron bolometer in the limiting case of a weak thermalization of non-equilibrium quasiparticles. We propose a new model relying on the non-thermal suppression of the superconducting energy gap by excess quasiparticles. Using material parameters typical for Al, we evaluate performance of the bolometer in the heterodyne regime at terahertz frequencies. Estimates show that the mixer may have quantum limited noise temperature and a few tens of GHz bandwidth, while the required local oscillator power is in the /spl mu/W range due to in-effective suppression of the energy gap by quasiparticles with high energies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1567
Permanent link to this record
 

 
Author (up) Semenov, A. D.; Gousev, Y. P.; Renk, K. F.; Voronov, B. M.; Gol'tsman, G. N.; Gershenzon, E. M.; Schwaab, G.W.; Feinaugle, R.
Title Noise characteristics of a NbN hot-electron mixer at 2.5 THz Type Journal Article
Year 1997 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 7 Issue 2 Pages 3572-3575
Keywords NbN HEB mixers
Abstract The noise temperature of a NbN phonon cooled hot-electron mixer has been measured at a frequency of 2.5 THz for various operating conditions. We obtained for optimal operation a double sideband mixer noise temperature of /spl ap/14000 K and a system conversion loss of /spl ap/23 dB at intermediate frequencies up to 1 GHz. The dependences of the mixer noise temperature on the bias voltage, local oscillator power, and intermediate frequency were consistent with the phenomenological description based on the effective temperature approximation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1594
Permanent link to this record
 

 
Author (up) Semenov, A. D.; Heusinger, M. A.; Renk, K. F.; Menschikov, E.; Sergeev, A. V.; Elant'ev, A. I.; Goghidze, I. G.; Gol'tsman, G. N.
Title Influence of phonon trapping on the performance of NbN kinetic inductance detectors Type Journal Article
Year 1997 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 7 Issue 2 Pages 3083-3086
Keywords NbN KID
Abstract Voltage and microwave photoresponse of NbN thin films to modulated and pulsed optical radiation reveals, far below the superconducting transition, a response time consistent with the lifetime of nonequilibrium quasiparticles. We show that even in 5 nm thick films at 4.2 K the phonon trapping is significant resulting in a quasiparticle lifetime of a few nanoseconds that is an order of magnitude larger than the recombination time. Values and temperature dependence of the quasiparticle lifetime obey the Bardeen-Cooper-Schrieffer theory and are in quantitative agreement with the electron-phonon relaxation rate determined from the resistive response near the superconducting transition. We discuss a positive effect of the phonon trapping on the performance of kinetic inductance detectors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1598
Permanent link to this record
 

 
Author (up) Shurakov, A.; Tong, C.-Y. E.; Blundell, R.; Kaurova, N.; Voronov, B.; Gol'tsman, G.
Title Microwave stabilization of a HEB mixer in a pulse-tube cryocooler Type Journal Article
Year 2013 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 23 Issue 3 Pages 1501504-1501504
Keywords NbN HEB mixers
Abstract We report the results of our study of the stability of an 800 GHz hot electron bolometer (HEB) mixer cooled with a pulse-tube cryocooler. Pulse-tube cryocoolers introduce temperature fluctuations as well as mechanical vibrations at a frequency of ~1 Hz, both of which can cause receiver gain fluctuations at that frequency. In our system, the motor of the cryocooler was separated from the cryostat to minimize mechanical vibrations, leaving thermal effects as the dominant source of the receiver gain fluctuations. We measured root mean square temperature variations of the 4 K stage of ~7 mK. The HEB mixer was pumped by a solid state local oscillator at 810 GHz. The root mean square current fluctuations at the low noise operating point (1.50 mV, 56.5 μA) were ~0.12 μA, and were predominantly due to thermal fluctuations. To stabilize the bias current, microwave radiation was injected to the HEB mixer. The injected power level was set by a proportional-integral-derivative controller, which completely compensates for the bias current oscillations induced by the pulse-tube cryocooler. Significant improvement in the Allan variance of the receiver output power was obtained, and an Allan time of 5 s was measured.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1372
Permanent link to this record
 

 
Author (up) Smirnov, K.; Moshkova, M.; Antipov, A.; Morozov, P.; Vakhtomin, Y.
Title The cascade switching of the photon number resolving superconducting single-photon detectors Type Journal Article
Year 2021 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 31 Issue 2 Pages 1-4
Keywords PNR SSPD, SNSPD
Abstract In this article, present the first detailed study of cascade switching in superconducting photon number resolving detectors. The detectors were made in the form of four parallel nanowires, coupled with the single-mode optical fiber and mounted into a closed-cycle refrigerator with a temperature of 2.1 K. We found out the value of additional false pulses (N cas.sw. ) appearing due to cascade switching and showed that it is possible to set up the detector bias current that corresponds to a high level of the detection efficiency and a low level of N cas.sw. simultaneously. We reached the detection efficiency of 60% and N cas.sw. = 0.3%.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1796
Permanent link to this record