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Author Kitaeva, G. K.; Kornienko, V. V.; Kuznetsov, K. A.; Pentin, I. V.; Smirnov, K. V.; Vakhtomin, Y. B.
Title Direct detection of the idler THz radiation generated by spontaneous parametric down-conversion Type Journal Article
Year 2019 Publication Opt. Lett. Abbreviated Journal (up) Opt. Lett.
Volume 44 Issue 5 Pages 1198-1201
Keywords HEB applications
Abstract We study parametric down-conversion (PDC) of optical laser radiation in the strongly frequency non-degenerate regime which is promising for the generation of quantum-correlated pairs of extremely different spectral ranges, the optical and the terahertz (THz) ones. The possibility to detect tenuous THz-frequency photon fluxes generated under low-gain spontaneous PDC is demonstrated using a hot electron bolometer. Then experimental dependences of the THz radiation power on the detection angle and on the pump intensity are analyzed.
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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 0146-9592 ISBN Medium
Area Expedition Conference
Notes PMID:30821747 Approved no
Call Number Serial 1801
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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 (up) 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.
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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 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1800
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Author Sidorova, M.; Semenov, A.; Hübers, H.-W.; Kuzmin, A.; Doerner, S.; Ilin, K.; Siegel, M.; Charaev, I.; Vodolazov, D.
Title Timing jitter in photon detection by straight superconducting nanowires: Effect of magnetic field and photon flux Type Journal Article
Year 2018 Publication Phys. Rev. B Abbreviated Journal (up) Phys. Rev. B
Volume 98 Issue 13 Pages 134504 (1 to 14)
Keywords SNSPD, NbN namowires
Abstract We studied the effects of the external magnetic field and photon flux on timing jitter in photon detection by straight superconducting NbN nanowires. At two wavelengths 800 and 1560 nm, statistical distribution in the appearance times of photon counts exhibits Gaussian shape at small times and an exponential tail at large times. The characteristic exponential time is larger for photons with smaller energy and increases with external magnetic field while variations in the Gaussian part of the distribution are less pronounced. Increasing photon flux drives the nanowire from the discrete quantum detection regime to the uniform bolometric regime that averages out fluctuations of the total number of nonequilibrium electrons created by the photon and drastically reduces jitter. The difference between standard deviations of Gaussian parts of distributions for these two regimes provides the measure for the strength of electron-number fluctuations; it increases with the photon energy. We show that the two-dimensional hot-spot detection model explains qualitatively the effect of magnetic field.
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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 2469-9950 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1842
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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 (up) 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.
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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 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 (up) 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 2724-0029 ISBN 978-88-85741-44-7 Medium
Area Expedition Conference 32nd European Modeling & Simulation Symposium
Notes Approved no
Call Number Serial 1839
Permanent link to this record