|   | 
Details
   web
Records
Author Гершензон, Е. М.; Литвак-Горская, Л. Б.; Луговая, Г. Я.; Шапиро, Е. З.
Title Об интерпретации отрицательного магнитосопротивления в случае проводимости по верхней зоне Хаббарда в n-Ge⟨Sb⟩ Type Journal Article
Year 1986 Publication Физика и техника полупроводников Abbreviated Journal Физика и техника полупроводников
Volume 20 Issue 1 Pages (up) 99-103
Keywords n-Ge, Hubbard upper zone conductivity, negative magnetoresistance
Abstract В рамках теории квантовых поправок к проводимости объяснено отрицательное магнитосопротивление в n-Ge с концентрацией доноров Nd≃2.8⋅1016÷1.1⋅1017см−3, наблюдаемое в диапазоне температур 4.2−10 K, когда основной вклад в проводимость дают электроны верхней зоны Хаббарда. Показано, что время релаксации фазы волновой функции τφ определяется временем электрон-фононного взаимодействия τeph.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1759
Permanent link to this record
 

 
Author Shangina, E. L.; Smirnov, K. V.; Morozov, D. V.; Kovalyuk, V. V.; Gol’tsman, G. N.; Verevkin, A. A.; Toropov, A. I.
Title Concentration dependence of the intermediate frequency bandwidth of submillimeter heterodyne AlGaAs/GaAs nanostructures Type Journal Article
Year 2010 Publication Bull. Russ. Acad. Sci. Phys. Abbreviated Journal Bull. Russ. Acad. Sci. Phys.
Volume 74 Issue 1 Pages (up) 100-102
Keywords 2DEG AlGaAs/GaAs heterostructures, THz heterodyne detectors, IF bandwidth
Abstract The concentration dependence of the intermediate frequency bandwidth of heterodyne AlGaAs/GaAs detectors with 2D electron gas is measured using submillimeter spectroscopy with high time resolution at T= 4.2 K. The intermediate frequency bandwidth f3dBfalls from 245 to 145 MHz with increasing concentration of 2D electrons n s = (1.6-6.6) × 10[su11] cm-2. The dependence f3dB ≈ n s – 0.04±is observed in the studied concentration range; this dependence is determined by electron scattering by the deformation potential of acoustic phonons and piezoelectric scattering.
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 1062-8738 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1217
Permanent link to this record
 

 
Author Chulkova, G.; Milostnaya, I.; Korneev, A.; Minaeva, O.; Rubtsova, I.; Voronov, B.; Okunev, O.; Smirnov, K.; Gol’tsman, G.; Kitaygorsky, J.; Cross, A.; Pearlman, A.; Sobolewski, R.; Slysz, W.
Title Superconducting nanostructures for counting of single photons in the infrared range Type Conference Article
Year 2005 Publication Proc. 2-nd CAOL Abbreviated Journal Proc. 2-nd CAOL
Volume 2 Issue Pages (up) 100-103
Keywords SSPD, SNSPD
Abstract We present our studies on ultrafast superconducting single-photon detectors (SSPDs) based on ultrathin NbN nanostructures. Our SSPDs are patterned by electron beam lithography from 4-nm thick NbN film into meander-shaped strips covering square area of 10/spl times/10 /spl mu/m/sup 2/. The advances in the fabrication technology allowed us to produce highly uniform 100-120-nm-wide strips with meander filling factor close to 0.6. The detectors exploit a combined detection mechanism, where upon a single-photon absorption, an avalanche of excited hot electrons and the biasing supercurrent, jointly produce a picosecond voltage transient response across the superconducting nanostrip. The SSPDs are typically operated at 4.2 K, but they have shown that their sensitivity in the infrared radiation range can be significantly improved by lowering the operating temperature from 4.2 K to 2 K. When operated at 2 K, the SSPD quantum efficiency (QE) for visible light photons reaches 30-40%, which is the saturation value limited by optical absorption of our 4-nm-thick NbN film. For 1.55 /spl mu/m photons, QE was /spl sim/20% and decreases exponentially with the increase of the optical wavelength, but even at the wavelength of 6 /spl mu/m the detector remains sensitive to single photons and exhibits QE of about 10/sup -2/%. The dark (false) count rate at 2 K is as low as 2 /spl times/ 10/sup -4/ s/sup -1/, what makes our detector essentially a background-limited sensor. The very low dark-count rate results in the noise equivalent power (NEP) as low as 10/sup -18/ WHz/sup -1/2/ for the mid-infrared range (6 /spl mu/m). Further improvement of the SSPD performance in the mid-infrared range can be obtained by substituting NbN for the other, lower-T/sub c/ superconductors with the narrow superconducting gap and low quasiparticle diffusivity. The use of such materials will shift the cutoff wavelength towards the values even longer than 6 /spl mu/m.
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 ISBN Medium
Area Expedition Conference Second International Conference on Advanced Optoelectronics and Lasers
Notes Approved no
Call Number Serial 1461
Permanent link to this record
 

 
Author Tovpeko, N. A.; Trifonov, A. V.; Semenov, A. V.; Antipov, S. V.; Kaurova, N. S.; Titova, N. A.; Goltsman, G. N.
Title Bandwidth performance of a THz normal metal TiN bolometer-mixer Type Conference Article
Year 2019 Publication Proc. 30th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 30th Int. Symp. Space Terahertz Technol.
Volume Issue Pages (up) 102-103
Keywords TiN normal metal bolometer, NMB
Abstract We report on the bandwidth performance of the normal metal TiN bolometer-mixer on top of an Al 2 O 3 substrate, which is capable to operate in a wide range of bath temperatures from 77 K – 300 K. The choice of the combination TiN / Al 2 O 3 is related to an advanced heat transport between the film and the substrate in this pair and the sufficient temperature coefficient of resistance. The data were taken at 132.5 – 145.5 GHz with two BWOs as a signal and an LO source. Measurements were taken on TiN films of different thickness starting from 20 nm down to 5 nm coupled into a spiral Au antenna, which improves matching of incoming radiation with the thin TiN fim. Our experiments demonstrate effective heat coupling from a TiN thin film to an Al 2 O 3 substrate (111) boosting gain bandwidth (GB) of TiN bolometer up to 6 GHz for 5 nm thin film. Current results indicate weak temperature dependence of GB on the bath temperature of the TiN bolometer. Theoretical estimations of GB performance meet with experimental data for 5 nm thin TiN films.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1279
Permanent link to this record
 

 
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 (up) 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.
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 0021-3640 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1164
Permanent link to this record
 

 
Author Gerecht, E.; Musante, C. F.; Jian, H.; Yngvesson, K. S.; Dickinson, J.; Waldman, J.; Gol'tsman, G. N.; Yagoubov, P. A.; Voronov, B. M.; Gershenzon, E. M.
Title Measured results for NbN phonon-cooled hot electron bolometric mixers at 0.6-0.75 THz, 1.56 THz, and 2.5 THz Type Conference Article
Year 1998 Publication Proc. 9th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 9th Int. Symp. Space Terahertz Technol.
Volume Issue Pages (up) 105-114
Keywords NbN HEB mixers
Abstract
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1587
Permanent link to this record
 

 
Author Verevkin, A.; Zhang, J.; Slysz, W.; Sobolewski, Roman; Lipatov, A.; Okunev, O.; Chulkova, G.; Korneev, A.; Smimov, K.; Gol'tsman, G. N.
Title Spectral sensitivity and temporal resolution of NbN superconducting single-photon detectors Type Conference Article
Year 2002 Publication Proc. 13th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 13th Int. Symp. Space Terahertz Technol.
Volume Issue Pages (up) 105-111
Keywords NbN SSPD, SNSPD
Abstract We report our studies on spectral sensitivity and time resolution of superconducting NbN thin film single-photon detectors (SPDs). Our SPDs exhibit an everimentally measured detection efficiencies (DE) from — 0.2% at 2=1550 nm up to —3% at lambda=405 nm wavelength for 10-nm film thickness devices and up to 3.5% at lambda=1550 nm for 3.5-nm film thickness devices. Spectral dependences of detection efficiency (DE) at 2=0.4 —3.0 pm range are presented. With variable optical delay setup, it is shown that NbN SPD potentially can resolve optical pulses with the repetition rate up to 10 GHz at least. The observed full width at the half maximum (FWHM) of the signal pulse is about 150-180 ps, limited by read-out electronics. The jitter of NbN SPD is measured to be —35 ps at optimum biasing.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1528
Permanent link to this record
 

 
Author Verevkin, A.; Gershenzon, E. M.; Gol'tsman, G. N.; Ptitsina, N. G.; Chulkova, G. M.; Smirnov, K. S.; Sobolewski, R.
Title Direct measurements of energy relaxation times in two-dimensional structures under quasi-equilibrium conditions Type Conference Article
Year 2002 Publication Mater. Sci. Forum Abbreviated Journal Mater. Sci. Forum
Volume 384-3 Issue Pages (up) 107-116
Keywords 2DEG, AlGaAs/GaAs
Abstract A new microwave technique was successfully applied for direct studies of energy relaxation times in two-dimensional AlGaAs/GaAs structures under quasi-equilibrium conditions in the nanosecond and picosecond time scale. We report our results of energy relaxation time measurements in the temperature range 1.6-50 K, in quantum Hall effect regime in magnetic fields up to 4 T.
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 ISBN Medium
Area Expedition Conference Materials Science Forum
Notes Approved no
Call Number Serial 1536
Permanent link to this record
 

 
Author Baryshev, A. M.; Wild, W.; Likhachev, S. F.; Vdovin, V. F.; Goltsman, G. N.; Kardashev, N. S.
Title Main parameters and instrumentation of Millimetron space mission Type Abstract
Year 2009 Publication Proc. 20th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 20th ISSTT
Volume Issue Pages (up) 108
Keywords SVLBI, Millimetron space observatory
Abstract Millimetron (official RosKosmos name ”Spectrum-M”) is a part of ambitious program called Spectrum intended to cover the whole electromagnetic spectrum with world class facilities. It is an approved mission included in Russian space program with the launch date in 2017..2019 time frame. The Millimetron satellite has a deployable 12 m diameter antenna with inner solid 4..6 m dish and a rim of petals. The mirror design is largely based on Radioastron mission concept that will be launched in 2009. If the antenna is passively cooled by radiation to open space, it would operate at approx. 50 K surface temperature, due to presence of a deployable three layer radiation screen. As a goal, there is a consideration of active cooling of antenna to 4 K, but this will depend on resources available to the project. Lagrangian libration point L2 considered for Millimetron orbit. There are four groups of scientific instruments envisioned: SVLBI instruments Space-Earth VLBI. It will allow to achieve unprecedented spatial resolution. Millimetron mission will attempt to achieve a mm/submm wave SVLBI. For that purpose, a SVLBI instrument covering selected ALMA bands and a standard VLBI band is envisioned, accompanied by a maser reference oscillator, a data digitizing and memory system, and a high speed data transmission link to ground. The ALMA bands can be extended to cover water lines if detector technology allows. Type of detector – heterodyne. Photometer/polarimeter. Recent progress in direct detector cameras with low spectral resolution, allows to propose a large format (5-10 kPixel) photometer camera on board of Millimetron mission. This camera can cover 0.1 – 2 THz region (with adequate amount of pixels per each subband). Wide band moderate resolution imaging spectrometer. Wide band moderate R = 1000 imaging spectrometer type instrument similar to SPICA SAFARI is planned, taking advantage of large cooled dish. It will cover the adequate spectral range allowable by antenna and will also work below 1 THz, as no ground instrument can have a cold main dish. High resolution spectrometer. For high resolution spectroscopy a heterodyne instrument is proposed, conceptually similar to HIFI on Herschel. This instrument will cover interesting frequency spots in 0.5..4 THz frequency range (using central part of antenna for higher frequency). It is sure that advances in LO and mixer technology will allow this frequency coverage.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1401
Permanent link to this record
 

 
Author Смирнов, А. В.; Карманцов, М. С.; Смирнов, К. В.; Вахтомин, Ю. Б.; Мастеров, Д. В.; Тархов, М. А.; Павлов, С. А.; Парафин, А. Е.
Title Терагерцовый отклик болометров на основе тонких пленок YBCO Type Journal Article
Year 2012 Publication ЖТФ Abbreviated Journal ЖТФ
Volume 82 Issue 12 Pages (up) 108-111
Keywords YBCO HEB NEP
Abstract Представлены первые результаты измерения болометрического отклика высокотемпературных сверхпроводниковых детекторов на основе тонких пленок YBCO на электромагнитное излучение с частотой 2.5 THz. Минимальное значение оптической мощности, эквивалентной шуму созданных детекторов, составило 3.5· 10-9 W/sqrt(Hz)sqrt. Обсуждена возможность дальнейшего увеличения чувствительности исследуемых детекторов.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Russian Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1825
Permanent link to this record