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Author Arutyunov, K. Y.; Ramos-Alvarez, A.; Semenov, A. V.; Korneeva, Y. P.; An, P. P.; Korneev, A. A.; Murphy, A.; Bezryadin, A.; Gol'tsman, G. N.
Title Superconductivity in highly disordered NbN nanowires Type Journal Article
Year 2016 Publication Nanotechnol. Abbreviated Journal Nanotechnol.
Volume 27 Issue 47 Pages 47lt02 (1 to 8)
Keywords NbN nanowires
Abstract The topic of superconductivity in strongly disordered materials has attracted significant attention. These materials appear to be rather promising for fabrication of various nanoscale devices such as bolometers and transition edge sensors of electromagnetic radiation. The vividly debated subject of intrinsic spatial inhomogeneity responsible for the non-Bardeen-Cooper-Schrieffer relation between the superconducting gap and the pairing potential is crucial both for understanding the fundamental issues of superconductivity in highly disordered superconductors, and for the operation of corresponding nanoelectronic devices. Here we report an experimental study of the electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. The temperature dependence of the critical current follows the textbook Ginzburg-Landau prediction for the quasi-one-dimensional superconducting channel I c approximately (1-T/T c)(3/2). We find that conventional models based on the the phase slip mechanism provide reasonable fits for the shape of R(T) transitions. Better agreement with R(T) data can be achieved assuming the existence of short 'weak links' with slightly reduced local critical temperature T c. Hence, one may conclude that an 'exotic' intrinsic electronic inhomogeneity either does not exist in our structures, or, if it does exist, it does not affect their resistive state properties, or does not provide any specific impact distinguishable from conventional weak links.
Address National Research University Higher School of Economics, Moscow Institute of Electronics and Mathematics,109028, Moscow, Russia. P L Kapitza Institute for Physical Problems RAS, Moscow, 119334, Russia
Corporate Author Thesis
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Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0957-4484 ISBN Medium
Area Expedition Conference
Notes PMID:27782000 Approved no
Call Number Serial 1332
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Author Korneeva, Y.; Sidorova, M.; Semenov, A.; Krasnosvobodtsev, S.; Mitsen, K.; Korneev, A.; Chulkova, G.; Goltsman, G.
Title Comparison of hot-spot formation in NbC and NbN single-photon detectors Type Journal Article
Year 2016 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 26 Issue 3 Pages 1-4
Keywords NbC, NbN SSPD, SNSPD
Abstract We report an experimental investigation of the hot-spot evolution in superconducting single-photon detectors made of disordered superconducting materials with different diffusivity and energy downconversion time values, i.e., 33-nm-thick NbN and 23-nm-thick NbC films. We have demonstrated that, in NbC film, only 405-nm photons produce sufficiently large hot spot to trigger a single-photon response. The dependence of detection efficiency on bias current for 405-nm photons in NbC is similar to that for 3400-nm photons in NbN. In NbC, large diffusivity and downconversion time result in 1-D critical current suppression profile compared with the usual 2-D profile in NbN.
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 (up) 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1348
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Author Fedorov, G. E.; Stepanova, T. S.; Gazaliev, A. S.; Gaiduchenko, I. A.; Kaurova, N. S.; Voronov, B. M.; Goltzman, G. N.
Title Asymmetric devices based on carbon nanotubes for terahertz-range radiation detection Type Journal Article
Year 2016 Publication Semicond. Abbreviated Journal Semicond.
Volume 50 Issue 12 Pages 1600-1603
Keywords carbon nanotubes, CNT detectors
Abstract Various asymmetric detecting devices based on carbon nanotubes (CNTs) are studied. The asymmetry is understood as inhomogeneous properties along the conducting channel. In the first type of devices, an inhomogeneous morphology of the CNT grid is used. In the second type of devices, metals with highly varying work functions are used as the contact material. The relation between the sensitivity and detector configuration is analyzed. Based on the data obtained, approaches to the development of an efficient detector of terahertz radiation, based on carbon nanotubes are proposed.
Address
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 1063-7826 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1776
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Author Iomdina, E. N.; Goltsman, G. N.; Seliverstov, S. V.; Sianosyan, A. A.; Teplyakova, K. O.; Rusova, A. A.
Title Study of transmittance and reflectance spectra of the cornea and the sclera in the THz frequency range Type Journal Article
Year 2016 Publication J. Biomed. Opt. Abbreviated Journal J. Biomed. Opt.
Volume 21 Issue 9 Pages 97002 (1 to 5)
Keywords BWO, IMPATT diode, Schottky diode, medicine, animals, cornea, physiology, humans, rabbits, sclera diagnostic imaging, physiology
Abstract An adequate water balance (hydration extent) is one of the basic factors of normal eye function, including its external shells: the cornea and the sclera. Adequate control of corneal and scleral hydration is very important for early diagnosis of a variety of eye diseases, stating indications for and contraindications against keratorefractive surgeries and the choice of contact lens correction solutions. THz systems of creating images in reflected beams are likely to become ideal instruments of noninvasive control of corneal and scleral hydration degrees. This paper reports on the results of a study involving transmittance and reflectance spectra for the cornea and the sclera of rabbit and human eyes, as well as those of the rabbit eye, in the frequency range of 0.13 to 0.32 THz. The dependence of the reflectance coefficient of these tissues on water mass percentage content was determined. The experiments were performed on three corneas, three rabbit scleras, two rabbit eyes, and three human scleras. The preliminary results demonstrate that the proposed technique, based on the use of a continuous THz radiation, may be utilized to create a device for noninvasive control of corneal and scleral hydration, which has clear potential of broad practical application.
Address Moscow State Pedagogical University, Department of Physics, 29 Malaya Pirogovskaya Street, Moscow 119435, Russia
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 1083-3668 ISBN Medium
Area Expedition Conference
Notes PMID:27626901 Approved no
Call Number Serial 1335
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Author Shcherbatenko, M.; Lobanov, Y.; Semenov, A.; Kovalyuk, V.; Korneev, A.; Ozhegov, R.; Kazakov, A.; Voronov, B.M.; Goltsman, G.N.
Title Potential of a superconducting photon counter for heterodyne detection at the telecommunication wavelength Type Journal Article
Year 2016 Publication Opt. Express Abbreviated Journal Opt. Express
Volume 24 Issue 26 Pages 30474-30484
Keywords NbN SSPD mixer, SNSPD
Abstract Here, we report on the successful operation of a NbN thin film superconducting nanowire single-photon detector (SNSPD) in a coherent mode (as a mixer) at the telecommunication wavelength of 1550 nm. Providing the local oscillator power of the order of a few picowatts, we were practically able to reach the quantum noise limited sensitivity. The intermediate frequency gain bandwidth (also referred to as response or conversion bandwidth) was limited by the spectral band of a single-photon response pulse of the detector, which is proportional to the detector size. We observed a gain bandwidth of 65 MHz and 140 MHz for 7 x 7 microm2 and 3 x 3 microm2 devices, respectively. A tiny amount of the required local oscillator power and wide gain and noise bandwidths, along with unnecessary low noise amplification, make this technology prominent for various applications, with the possibility for future development of a photon counting heterodyne-born large-scale array.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 1094-4087 ISBN Medium
Area Expedition Conference
Notes PMID:28059394 Approved no
Call Number Serial 1207
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