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Author Ovchinnikov, O. V.; Perepelitsa, A. S.; Smirnov, M. S.; Latyshev, A. N.; Grevtseva, I. G.; Vasiliev, R. B.; Goltsman, G. N.; Vitukhnovsky, A. G.
Title Luminescence of colloidal Ag2S/ZnS core/shell quantum dots capped with thioglycolic acid Type Journal Article
Year (down) 2020 Publication J. Luminescence Abbreviated Journal J. Luminescence
Volume 220 Issue Pages 117008 (1 to 7)
Keywords Ag2S QD, quantum dots
Abstract The features of IR luminescence of colloidal AgS QDs passivated with thioglycolic acid (AgS/TGA) under the formation of AgS/ZnS/TGA core/shell QDs are considered. A 4.5-fold increase in the quantum yield of recombination IR luminescence within the band with a peak at 960 nm (1.29 eV), full width at half maximum of 250 nm (0.34 eV), and the Stokes shift with respect to the exciton absorption of 0.6 eV was found. The increase in the IR luminescence intensity of AgS/ZnS/TGA QDs is accompanied by an increase in the average luminescence lifetime from 2.9 ns to 14.3 ns, which is explained as “healing” of surface trap states during the formation of the ZnS shell. For the first time, the enhancement of the luminescence intensity photodegradation (hereinafter referred to as fatigue) was found during the formation of the AgS/ZnS/TGA core/shell QDs. The luminescence fatigue is irreversible. We conclude that the initial stage of photolysis of the AgS core QDs under laser irradiation plays a key role. Low-atomic photolytic clusters of silver formed on the AgS core QDs act as luminescence quenching centers and do not reveal structural transformations into AgS, provided that the clusters are not in contact with TGA.
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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 0022-2313 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1267
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Author Pentin, I.; Vakhtomin, Y.; Seleznev, V.; Smirnov, K.
Title Hot electron energy relaxation time in vanadium nitride superconducting film structures under THz and IR radiation Type Journal Article
Year (down) 2020 Publication Sci. Rep. Abbreviated Journal Sci. Rep.
Volume 10 Issue 1 Pages 16819
Keywords VN HEB
Abstract The paper presents the experimental results of studying the dynamics of electron energy relaxation in structures made of thin (d approximately 6 nm) disordered superconducting vanadium nitride (VN) films converted to a resistive state by high-frequency radiation and transport current. Under conditions of quasi-equilibrium superconductivity and temperature range close to critical (~ Tc), a direct measurement of the energy relaxation time of electrons by the beats method arising from two monochromatic sources with close frequencies radiation in sub-THz region (omega approximately 0.140 THz) and sources in the IR region (omega approximately 193 THz) was conducted. The measured time of energy relaxation of electrons in the studied VN structures upon heating of THz and IR radiation completely coincided and amounted to (2.6-2.7) ns. The studied response of VN structures to IR (omega approximately 193 THz) picosecond laser pulses also allowed us to estimate the energy relaxation time in VN structures, which was ~ 2.8 ns and is in good agreement with the result obtained by the mixing method. Also, we present the experimentally measured volt-watt responsivity (S~) within the frequency range omega approximately (0.3-6) THz VN HEB detector. The estimated values of noise equivalent power (NEP) for VN HEB and its minimum energy level (deltaE) reached NEP@1MHz approximately 6.3 x 10(-14) W/ radicalHz and deltaE approximately 8.1 x 10(-18) J, respectively.
Address National Research University Higher School of Economics, 20 Myasnitskaya Str., Moscow, 101000, Russia
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 2045-2322 ISBN Medium
Area Expedition Conference
Notes PMID:33033360; PMCID:PMC7546726 Approved no
Call Number Serial 1797
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Author Rasulova, G. K.; Pentin, I. V.; Vakhtomin, Y. B.; Smirnov, K. V.; Khabibullin, R. A.; Klimov, E. A.; Klochkov, A. N.; Goltsman, G. N.
Title Pulsed terahertz radiation from a double-barrier resonant tunneling diode biased into self-oscillation regime Type Journal Article
Year (down) 2020 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 128 Issue 22 Pages 224303 (1 to 11)
Keywords HEB, resonant tunneling diode, RTD
Abstract The study of the bolometer response to terahertz (THz) radiation from a double-barrier resonant tunneling diode (RTD) biased into the negative differential conductivity region of the I–V characteristic revealed that the RTD emits two pulses in a period of intrinsic self-oscillations of current. The bolometer pulse repetition rate is a multiple of the fundamental frequency of the intrinsic self-oscillations of current. The bolometer pulses are detected at two critical points with a distance between them being half or one-third of a period of the current self-oscillations. An analysis of the current self-oscillations and the bolometer response has shown that the THz photon emission is excited when the tunneling electrons are trapped in (the first pulse) and then released from (the second pulse) miniband states.
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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 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1262
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Author Shcherbatenko, M. L.; Elezov, M. S.; Goltsman, G. N.; Sych, D. V.
Title Sub-shot-noise-limited fiber-optic quantum receiver Type Journal Article
Year (down) 2020 Publication Phys. Rev. A Abbreviated Journal Phys. Rev. A
Volume 101 Issue 3 Pages 032306 (1 to 5)
Keywords SSPD mixer, SNSPD
Abstract We experimentally demonstrate a quantum receiver based on the Kennedy scheme for discrimination between two phase-modulated weak coherent states. The receiver is assembled entirely from standard fiber-optic elements and operates at a conventional telecom wavelength of 1.55 μm. The local oscillator and the signal are transmitted through different optical fibers, and the displaced signal is measured with a high-efficiency superconducting nanowire single-photon detector. We show the discrimination error rate is two times below that of a shot-noise-limited receiver with the same system detection efficiency.
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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 2469-9926 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1268
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Author Shein, K. V.; Zarudneva, A. A.; Emel’yanova, V. O.; Logunova, M. A.; Chichkov, V. I.; Sobolev, A.S.; Zav’yalov, V. V.; Lehtinen, J. S.; Smirnov, E. O.; Korneeva, Y. P.; Korneev, A. A.; Arutyunov, K. Y.
Title Superconducting microstructures with high impedance Type Journal Article
Year (down) 2020 Publication Phys. Solid State Abbreviated Journal Phys. Solid State
Volume 62 Issue 9 Pages 1539-1542
Keywords superconducting channels, SIS, inetic inductance, tunneling contacts, high impedance
Abstract The transport properties of two types of quasi-one-dimensional superconducting microstructures were investigated at ultra-low temperatures: the narrow channels close-packed in the shape of meander, and the chains of tunneling contacts “superconductor-insulator-superconductor.” Both types of the microstructures demonstrated high value of high-frequency impedance and-or the dynamic resistance. The study opens up potential for using of such structures as current stabilizing elements with zero dissipation.
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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 1063-7834 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1789
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