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Author Kuzin, Aleksei; Elmanov, Ilia; Kovalyuk, Vadim; An, Pavel; Goltsman, Gregory
Title Silicon nitride focusing grating coupler for input and output light of NV-centers Type Conference Article
Year 2020 Publication Proc. 32-nd EMSS Abbreviated Journal Proc. 32-nd EMSS
Volume Issue Pages 349-353
Keywords NV-centers, focusing grating coupler
Abstract Here we presented the numerical results for the calculation of focusing grating coupler efficiency in the visible wavelength range. Using the finite element method, the optimal geometric parameters, including filling factor and grating period for a central wavelength of 637 nm, were found. Obtained results allow to input/output single-photon radiation from NV-centers, and can be used for research and development of a scalable on-chip quantum optical computing.
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 (down) 2724-0029 ISBN 978-88-85741-44-7 Medium
Area Expedition Conference 32nd European Modeling & Simulation Symposium
Notes Approved no
Call Number Serial 1841
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Author Elmanov, Ilia; Elmanova, Anna; Kovalyuk, Vadim; An, Pavel; Goltsman, Gregory
Title Integrated contra-directional coupler for NV-centers photon filtering Type Conference Article
Year 2020 Publication Proc. 32-nd EMSS Abbreviated Journal Proc. 32-nd EMSS
Volume Issue Pages 354-360
Keywords NV-centers, nanodiamonds, quantum photonic integrated circuits, contra-direction coupler, Bragg gratings
Abstract We modelled an integrated optical contra-directional coupler on silicon nitride platform. Performance of the filter was studied depending on different parameters, including the grating period and the height of teeth of the Bragg grating near 637 nm operation wavelength. The obtained results can be used for a design and fabrication of quantum photonic integrated circuits with on-chip single-photon NV-centers in nanodiamonds.
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 (down) 2724-0029 ISBN 978-88-85741-44-7 Medium
Area Expedition Conference 32nd European Modeling & Simulation Symposium
Notes Approved no
Call Number Serial 1839
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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
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 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 Sidorova, M.; Semenov, Alexej D.; Hübers, H.-W.; Ilin, K.; Siegel, M.; Charaev, I.; Moshkova, M.; Kaurova, N.; Goltsman, G. N.; Zhang, X.; Schilling, A.
Title Electron energy relaxation in disordered superconducting NbN films Type Journal Article
Year 2020 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 102 Issue 5 Pages 054501 (1 to 15)
Keywords NbN SSPD, SNSPD, HEB, bandwidth, relaxation time
Abstract We report on the inelastic-scattering rate of electrons on phonons and relaxation of electron energy studied by means of magnetoconductance, and photoresponse, respectively, in a series of strongly disordered superconducting NbN films. The studied films with thicknesses in the range from 3 to 33 nm are characterized by different Ioffe-Regel parameters but an almost constant product qTl (qT is the wave vector of thermal phonons and l is the elastic mean free path of electrons). In the temperature range 14–30 K, the electron-phonon scattering rates obey temperature dependencies close to the power law 1/τe−ph∼Tn with the exponents n≈3.2–3.8. We found that in this temperature range τe−ph and n of studied films vary weakly with the thickness and square resistance. At 10 K electron-phonon scattering times are in the range 11.9–17.5 ps. The data extracted from magnetoconductance measurements were used to describe the experimental photoresponse with the two-temperature model. For thick films, the photoresponse is reasonably well described without fitting parameters, however, for thinner films, the fit requires a smaller heat capacity of phonons. We attribute this finding to the reduced density of phonon states in thin films at low temperatures. We also show that the estimated Debye temperature in the studied NbN films is noticeably smaller than in bulk material.
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 (down) 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1266
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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
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1800
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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 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.
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 (down) 2469-9926 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1268
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Author Vodolazov, D. Y.; Manova, N. N.; Korneeva, Y. P.; Korneev, A. A.
Title Timing jitter in NbN superconducting microstrip single-photon detector Type Journal Article
Year 2020 Publication Phys. Rev. Applied Abbreviated Journal Phys. Rev. Applied
Volume 14 Issue 4 Pages 044041 (1 to 8)
Keywords NbN SSPD, SNSPD
Abstract We experimentally study timing jitter of single-photon detection by NbN superconducting strips with width w ranging from 190 nm to 3μm. We find that timing jitter of both narrow (190 nm) and micron-wide strips is about 40 ps at currents where internal detection efficiency η saturates and it is close to our instrumental jitter. We also calculate intrinsic timing jitter in wide strips using the modified time-dependent Ginzburg-Landau equation coupled with a two-temperature model. We find that with increasing width the intrinsic timing jitter increases and the effect is most considerable at currents where a rapid growth of η changes to saturation. We relate it with complicated vortex and antivortex dynamics, which depends on a photon’s absorption site across the strip and its width. The model also predicts that at current close to depairing current the intrinsic timing jitter of a wide strip could be about ℏ/kBTc (Tc is a critical temperature of superconductor), i.e., the same as for a narrow strip.
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 (down) 2331-7019 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1788
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Author Korneeva, Y. P.; Manova, N. N.; Florya, I. N.; Mikhailov, M. Y.; Dobrovolskiy, O. V.; Korneev, A. A.; Vodolazov, D. Y.
Title Different single-photon response of wide and narrow superconducting MoxSi1−x strips Type Journal Article
Year 2020 Publication Phys. Rev. Applied Abbreviated Journal Phys. Rev. Applied
Volume 13 Issue 2 Pages 024011 (1 to 7)
Keywords MoSi SSPD, SNSPD
Abstract The photon count rate (PCR) of superconducting single-photon detectors made of MoxSi1−x films shaped as a 2-μm-wide strip and a 115-nm-wide meander strip line is studied experimentally as a function of the dc biasing current at different values of the perpendicular magnetic field. For the wide strip, a crossover current Icross is observed, below which the PCR increases with an increasing magnetic field and above which it decreases. This behavior contrasts with the narrow MoxSi1−x meander, for which no crossover current is observed, thus suggesting different photon-detection mechanisms in the wide and narrow strips. Namely, we argue that in the wide strip the absorbed photon destroys superconductivity locally via the vortex-antivortex mechanism for the emergence of resistance, while in the narrow meander superconductivity is destroyed across the whole strip line, forming a hot belt. Accordingly, the different photon-detection mechanisms associated with vortices and the hot belt determine the qualitative difference in the dependence of the PCR on the magnetic field.
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 (down) 2331-7019 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1790
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Author Tretyakov, I.; Svyatodukh, S.; Perepelitsa, A.; Ryabchun, S.; Kaurova, N.; Shurakov, A.; Smirnov, M.; Ovchinnikov, O.; Goltsman, G.
Title Ag2S QDs/Si heterostructure-based ultrasensitive SWIR range detector Type Journal Article
Year 2020 Publication Nanomaterials (Basel) Abbreviated Journal Nanomaterials (Basel)
Volume 10 Issue 5 Pages 1-12
Keywords detector; quantum dots; short-wave infrared range; silicon
Abstract In the 20(th) century, microelectronics was revolutionized by silicon-its semiconducting properties finally made it possible to reduce the size of electronic components to a few nanometers. The ability to control the semiconducting properties of Si on the nanometer scale promises a breakthrough in the development of Si-based technologies. In this paper, we present the results of our experimental studies of the photovoltaic effect in Ag2S QD/Si heterostructures in the short-wave infrared range. At room temperature, the Ag2S/Si heterostructures offer a noise-equivalent power of 1.1 x 10(-10) W/ radicalHz. The spectral analysis of the photoresponse of the Ag2S/Si heterostructures has made it possible to identify two main mechanisms behind it: the absorption of IR radiation by defects in the crystalline structure of the Ag2S QDs or by quantum QD-induced surface states in Si. This study has demonstrated an effective and low-cost way to create a sensitive room temperature SWIR photodetector which would be compatible with the Si complementary metal oxide semiconductor technology.
Address Laboratory of nonlinear optics, Zavoisky Physical-Technical Institute of the Russian Academy of Sciences, Kazan 420029, 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 (down) 2079-4991 ISBN Medium
Area Expedition Conference
Notes PMID:32365694; PMCID:PMC7712218 Approved no
Call Number Serial 1151
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Author Gorokhov, G.; Bychanok, D.; Gayduchenko, I.; Rogov, Y.; Zhukova, E.; Zhukov, S.; Kadyrov, L.; Fedorov, G.; Ivanov, E.; Kotsilkova, R.; Macutkevic, J.; Kuzhir, P.
Title THz spectroscopy as a versatile tool for filler distribution diagnostics in polymer nanocomposites Type Journal Article
Year 2020 Publication Polymers (Basel) Abbreviated Journal Polymers (Basel)
Volume 12 Issue 12 Pages 3037 (1 to 14)
Keywords THz spectroscopy; nanocomposites, percolation threshold, time-domain spectroscopy, time-domain spectrometer, TDS
Abstract Polymer composites containing nanocarbon fillers are under intensive investigation worldwide due to their remarkable electromagnetic properties distinguished not only by components as such, but the distribution and interaction of the fillers inside the polymer matrix. The theory herein reveals that a particular effect connected with the homogeneity of a composite manifests itself in the terahertz range. Transmission time-domain terahertz spectroscopy was applied to the investigation of nanocomposites obtained by co-extrusion of PLA polymer with additions of graphene nanoplatelets and multi-walled carbon nanotubes. The THz peak of permittivity's imaginary part predicted by the applied model was experimentally shown for GNP-containing composites both below and above the percolation threshold. The physical nature of the peak was explained by the impact on filler particles excluded from the percolation network due to the peculiarities of filler distribution. Terahertz spectroscopy as a versatile instrument of filler distribution diagnostics is discussed.
Address Institute of Photonics, University of Eastern Finland, Yliopistokatu 7, FI-80101 Joensuu, Finland
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 (down) 2073-4360 ISBN Medium
Area Expedition Conference
Notes PMID:33353036; PMCID:PMC7767186 Approved no
Call Number Serial 1780
Permanent link to this record