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Author Zvagelsky, R. D.; Chubich, D. A.; Kolymagin, D. A.; Korostylev, E. V.; Kovalyuk, V. V.; Prokhodtsov, A. I.; Tarasov, A. V.; Goltsman, G. N.; Vitukhnovsky, A. G.
Title Three-dimensional polymer wire bonds on a chip: morphology and functionality Type Journal Article
Year 2020 Publication J. Phys. D: Appl. Phys. Abbreviated Journal J. Phys. D: Appl. Phys.
Volume 53 Issue 35 Pages (down) 355102
Keywords photonic wire bonds, PWB
Abstract Modern microchip-scale transceivers are capable of transmitting data at rates of the order of several terabits per second. In this regard, there is an urgent need to improve the interfaces connecting the chips and extend the bandpass of the interconnections. We use an approach combining silicon nitride nanophotonic circuits with 3D polymer waveguides fabricated by direct laser writing, which can be used as photonic interconnections or photonic wire bonds (PWB). These structures are designed, simulated, fabricated, and optimized for better light transmission at the telecommunication wavelength. An important part of this work is the study of the telecom signal transmission in a 3D polymer waveguide connecting two silicon nitride facing tapers. Two cases are considered: the tapers are one opposite the other or misaligned. Initially, the PWB shape was chosen to be Gaussian and then optimized: the top was circle-shaped and with the lower part still being Gaussian. Transmission losses were measured for both types of waveguides with different shapes. The idea of an optical multi-level crossing for photonic integrated circuits is also suggested as a solution to the problem of interconnections within a single chip.
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 0022-3727 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1181
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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 2020 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 128 Issue 22 Pages (down) 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.
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 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1262
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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 2020 Publication J. Luminescence Abbreviated Journal J. Luminescence
Volume 220 Issue Pages (down) 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.
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 0022-2313 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1267
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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 (down) 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 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1800
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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 (down) 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 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1266
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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 (down) 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 2331-7019 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1788
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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 (down) 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 2469-9926 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1268
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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 (down) 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 2331-7019 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1790
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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 (down) 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 Dryazgov, M.; Semenov, A.; Manova, N.; Korneeva, Y.; Korneev, A.
Title Modelling of normal domain evolution after single-photon absorption of a superconducting strip of micron width Type Conference Article
Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1695 Issue Pages (down) 012195 (1 to 4)
Keywords SSPD modelling, SNSPD
Abstract The present paper describes a modelling of normal domain evolution in superconducting strip of micron width using solving differential equations describing the temperature and current changes. The solving results are compared with experimental data. This comparison demonstrates the high accuracy of the model. In future, it is possible to employ this model for improvement of single photon detector based on micron-scale superconducting strips.
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 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1785
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Author Titova, N. A.; Baeva, E. M.; Kardakova, A. I.; Goltsman, G. N.
Title Fabrication of NbN/SiNx:H/SiO2 membrane structures for study of heat conduction at low temperatures Type Conference Article
Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1695 Issue Pages (down) 012190
Keywords NbN films, insulating membrane
Abstract Here we report on the development of NbN/SiNx:H/SiO2-membrane structures for investigation of the thermal transport at low temperatures. Thin NbN films are known to be in the regime of a strong electron-phonon coupling, and one can assume that the phononic and electronic baths in the NbN are in local equilibrium. In such case, the cooling of the NbN-based devices strongly depends on acoustic matching to the substrate and substrate thermal characteristics. For the insulating membrane much thicker than the NbN film, our preliminary results demonstrate that the membrane serves as an additional channel for the thermal relaxation of the NbN sample. That implies a negligible role of thermal boundary resistance of the NbN-SiNx:H interface in comparison with the internal thermal resistance of the insulating membrane.
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 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1165
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Author Shurakov, A.; Prikhodko, A.; Mikhailov, D.; Belikov, I.; Kaurova, N.; Voronov, B.; Goltsman, G.
Title Efficiency of a microwave reflectometry for readout of a THz multipixel Schottky diode direct detector Type Conference Article
Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1695 Issue Pages (down) 012156
Keywords Shottky diode, THz, direct detector, multipixel camera
Abstract In this paper we report on the results of investigation of efficiency of a microwave reflectometry for readout of a terahertz multipixel Schottky diode direct detector. Decent capabilities of the microwave reflectometry readout were earlier justified by us for a hot electron bolometric direct detector. In case of a planar Schottky diode, we observed increase of an optical noise equivalent power by a factor of 2 compared to that measured within a conventional readout scheme. For implementation of a multipixel camera, a microwave reflectometer is to be used to readout each row of the camera, and the row switching is to be maintained by a CMOS analog multiplexer. The diodes within a row have to be equipped with filters to distribute the probing microwave signal properly. The simultaneous use of analog multiplexing and microwave reflectometry enables to reduce the camera response time by a factor of its number of columns.
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 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1153
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Author Shurakov, A.; Mikhailov, D.; Belikov, I.; Kaurova, N.; Zilberley, T.; Prikhodko, A.; Voronov, B.; Vasil’evskii, I.; Goltsman, G.
Title Planar Schottky diode with a Γ-shaped anode suspended bridge Type Conference Article
Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1695 Issue Pages (down) 012154
Keywords Schottky diode, GaAs, InP substrate
Abstract In this paper we report on the fabrication of a planar Schottky diode utilizing a Г-shaped anode suspended bridge. The bridge maintains transition between the top and bottom level planes of a 1.4 µm thick GaAs mesa. To implement the profile of a suspended bridge and inward tilt of a mesa wall adjacent to it, we make use of an anisotropic etching of gallium arsenide. The geometry proposed enables the fabrication of a diode with mesa of an arbitrary thickness to mitigate AC losses in the diode layered structure at terahertz frequencies of interest. For frequencies beyond 1 THz, it is also beneficial to use the geometry for the implementation of n-GaAs/n-InGaAs heterojunction Schottky diodes grown on InP substrate.
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 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1152
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Author Polyakova, M. I.; Korneev, A. A.; Semenov, A. V.
Title Comparison single- and double- spot detection efficiencies of SSPD based to MoSi and NbN films Type Conference Article
Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1695 Issue Pages (down) 012146 (1 to 3)
Keywords NbN SSPD, SNSPD, MoSi
Abstract In this work, we present results of quantum detector tomography of superconducting single photon detector (SSPD) based on MoSi film, and compare them with previously reported data on NbN. We find that for both materials hot spot interaction length coincides with the strip width, and the dependence of single and double-spot detection efficiencies on bias current are compatible with sufficiently large hot-spot size, approaching the strip width.
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 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1787
Permanent link to this record
 

 
Author Shcherbatenko, M.; Elezov, M.; Sych, D.; Goltsman, G. N.
Title Optimal fiber optic scheme for sub-SQL quantum receiver realization Type Conference Article
Year 2020 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1695 Issue Pages (down) 012140
Keywords sub-SQL, below quantum limit, QL, system quantum limit, SQL
Abstract Practical implementation of high-precision quantum measurements is an important problem in modern science. One of the main parts of the quantum receiver is the optical scheme. We developed and tested several optical circuits based on different types of interferometers, namely Sagnac-based scheme, Mach-Zehnder-based scheme, and Michelson-based scheme. All these schemes are assembled with optical fibers and fiber-optic components, since the fiber-optic implementation is closest to application in practical devices. Schemes were evaluated according to two main criteria: extinction and interference stability. On the basis of the obtained data, it can be concluded that the most suitable is the scheme based on the Mach-Zehnder interferometer. In continuous mode, we were able to obtain an interference extinction about 30 dB with acceptable temporal stability.
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 1742-6588 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1265
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