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Author Elmanov, Ilia; Elmanova, Anna; Kovalyuk, Vadim; An, Pavel; Goltsman, Gregory
Title Silicon nitride photonic crystal cavity coupled with NV-centers in nanodiamonds Type Conference Article
Year 2020 Publication Proc. 32-nd EMSS Abbreviated Journal Proc. 32-nd EMSS
Volume Issue Pages 344-348
Keywords
Abstract The development of integrated quantum photonics requires a high efficient excitation and coupling of a single photon source with on-chip devices. In this paper, we show our results of modelling for high-Q photonic crystal cavity, optimized for zero phonon line emission of NV-centers in nanodiamonds. Modelling was performed for the silicon nitride platform and obtained a quality factor equals to 6136 at 637 nm wavelength.
Address NV-centers, nanodiamonds
Corporate Author Thesis (up)
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2724-0029 ISBN 978-88-85741-44-7 Medium
Area Expedition Conference 32nd European Modeling & Simulation Symposium
Notes Approved no
Call Number Serial 1840
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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 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 (up)
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 Vasilev, D. D.; Malevannaya, E. I.; Moiseev, K. M.; Zolotov, P. I.; Antipov, A. V.; Vakhtomin, Y. B.; Smirnov, K. V.
Title Influence of deposited material energy on superconducting properties of the WSi films Type Conference Article
Year 2020 Publication IOP Conf. Ser.: Mater. Sci. Eng. Abbreviated Journal IOP Conf. Ser.: Mater. Sci. Eng.
Volume 781 Issue Pages 012013 (1 to 6)
Keywords WSi SSPD, SNSPD
Abstract WSi thin films have the advantages for creating SNSPDs with a large active area or array of detectors on a single substrate due to the amorphous structure. The superconducting properties of ultrathin WSi films substantially depends on their structure and thickness as the NbN films. Scientific groups investigating WSi films mainly focused only on changes of their thickness and the ratio of the components on the substrate at room temperature. This paper presents experiments to determine the effect of the bias potential on the substrate, the temperature of the substrate, and the peak power of pulsed magnetron sputtering, which is the equivalent of ionization, a tungsten target, on the surface resistance and superconducting properties of the WSi ultrathin films. The negative effect of the substrate temperature and the positive effect of the bias potential and the ionization coefficient (peak current) allow one to choose the best WSi films formation mode for SNSPD: substrate temperature 297 K, bias potential -60 V, and peak current 3.5 A.
Address
Corporate Author Thesis (up)
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1757-899X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1798
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Author Antipov, A. V.; Seleznev, V. A.; Vakhtomin, Y. B.; Morozov, P. V.; Vasilev, D. D.; Malevannaya, E. I.; Moiseev, K. M.; Smirnov, K.
Title Investigation of WSi and NbN superconducting single-photon detectors in mid-IR range Type Conference Article
Year 2020 Publication IOP Conf. Ser.: Mater. Sci. Eng. Abbreviated Journal IOP Conf. Ser.: Mater. Sci. Eng.
Volume 781 Issue Pages 012011 (1 to 5)
Keywords WSi, NbN SSPD, SNSPD
Abstract Spectral characteristics of WSi and NbN superconducting single-photon detectors with different surface resistance and width of nanowire strips have been investigated in the wavelength range of 1.3-2.5 μm. WSi structures with narrower strips demonstrated better performance for detection of single photons in longer wavelength range. The difference in normalized photon count rate for such structures reaches one order of magnitude higher in comparison with structures based on NbN thin films at 2.5 μm.
Address
Corporate Author Thesis (up)
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1757-899X ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1799
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Author Zhang, X.; Lita, A. E.; Smirnov, K.; Liu, H. L.; Zhu, D.; Verma, V. B.; Nam, S. W.; Schilling, A.
Title Strong suppression of the resistivity near the superconducting transition in narrow microbridges in external magnetic fields Type Journal Article
Year 2020 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 101 Issue 6 Pages 060508 (1 to 6)
Keywords MoSi, WSi films
Abstract We have investigated a series of superconducting bridges based on homogeneous amorphous WSi and MoSi films, with bridge widths w ranging from 2 to 1000μm and film thicknesses d∼4−6 and 100 nm. Upon decreasing the bridge widths below the respective Pearl lengths, we observe in all cases distinct changes in the characteristics of the resistive transitions to superconductivity. For each of the films, the resistivity curves R(B,T) separate at a well-defined and field-dependent temperature T∗(B) with decreasing the temperature, resulting in a dramatic suppression of the resistivity and a sharpening of the transitions with decreasing bridge width w. The associated excess conductivity in all the bridges scales as 1/w, which may suggest either the presence of a highly conducting region that is dominating the electric transport, or a change in the vortex dynamics in narrow enough bridges. We argue that this effect can only be observed in materials with sufficiently weak vortex pinning.
Address
Corporate Author Thesis (up)
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1800
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