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Author | Tretyakov, I.; Shurakov, A.; Perepelitsa, A.; Kaurova, N.; Svyatodukh, S.; Zilberley, T.; Ryabchun, S.; Smirnov, M.; Ovchinnikov, O.; Goltsman, G. | ||||
Title | Room temperature silicon detector for IR range coated with Ag2S quantum dots | Type | Journal Article | ||
Year | 2019 | Publication | Phys. Status Solidi RRL | Abbreviated Journal | Phys. Status Solidi RRL |
Volume | 13 | Issue | 9 | Pages | 1900187-(1-6) |
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Abstract | For decades, silicon has been the chief technological semiconducting material of modern microelectronics and has a strong influence on all aspects of the society. Applications of Si-based optoelectronic devices are limited to the visible and near infrared (IR) ranges. For photons with an energy less than 1.12 eV, silicon is almost transparent. The expansion of the Si absorption to shorter wavelengths of the IR range is of considerable interest for optoelectronic applications. By creating impurity states in Si, it is possible to cause sub-bandgap photon absorption. Herein, an elegant and effective technology of extending the photo-response of Si toward the IR range is presented. This approach is based on the use of Ag 2 S quantum dots (QDs) planted on the surface of Si to create impurity states in the Si bandgap. The specific sensitivity of the room temperature zero-bias Si_Ag 2 Sp detector is 10 11 cm Hz W 1 at 1.55 μm. Given the variety of available QDs and the ease of extending the photo-response of Si toward the IR range, these findings open a path toward future studies and development of Si detectors for technological applications. The current research at the interface of physics and chemistry is also of fundamental importance to the development of Si optoelectronics. | ||||
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ISSN | 1862-6254 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1149 | |||
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Author | Saveskul, N. A.; Titova, N. A.; Baeva, E. M.; Semenov, A. V.; Lubenchenko, A. V.; Saha, S.; Reddy, H.; Bogdanov, S. I.; Marinero, E. E.; Shalaev, V. M.; Boltasseva, A.; Khrapai, V. S.; Kardakova, A. I.; Goltsman, G. N. | ||||
Title | Superconductivity behavior in epitaxial TiN films points to surface magnetic disorder | Type | Journal Article | ||
Year | 2019 | Publication | Phys. Rev. Applied | Abbreviated Journal | Phys. Rev. Applied |
Volume | 12 | Issue | 5 | Pages | 054001 |
Keywords | epitaxial TiN films | ||||
Abstract | We analyze the evolution of the normal and superconducting properties of epitaxial TiN films, characterized by high Ioffe-Regel parameter values, as a function of the film thickness. As the film thickness decreases, we observe an increase of the residual resistivity, that becomes dominated by diffusive surface scattering for d≤20nm. At the same time, a substantial thickness-dependent reduction of the superconducting critical temperature is observed compared to the bulk TiN value. In such high-quality material films, this effect can be explained by a weak magnetic disorder residing in the surface layer with a characteristic magnetic defect density of approximately 1012cm−2. Our results suggest that surface magnetic disorder is generally present in oxidized TiN films. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 2331-7019 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1166 | |||
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Author | Ferrari, S.; Kovalyuk, V.; Vetter, A.; Lee, C.; Rockstuhl, C.; Semenov, A.; Gol'tsman, G.; Pernice, W. | ||||
Title | Analysis of the detection response of waveguide-integrated superconducting nanowire single-photon detectors at high count rate | Type | Journal Article | ||
Year | 2019 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 115 | Issue | 10 | Pages | 101104 |
Keywords | SSPD, SNSPD, waveguide | ||||
Abstract | Nanophotonic circuitry and superconducting nanowires have been successfully combined for detecting single photons, propagating in an integrated photonic circuit, with high efficiency and low noise and timing uncertainty. Waveguide-integrated superconducting nanowire single-photon detectors (SNSPDs) can nowadays be engineered to achieve subnanosecond recovery times and can potentially be adopted for applications requiring Gcps count rates. However, particular attention shall be paid to such an extreme count rate regime since artifacts in the detector functionality emerge. In particular, a count-rate dependent detection efficiency has been encountered that can compromise the accuracy of quantum detector tomography experiments. Here, we investigate the response of waveguide-integrated SNSPDs at high photon flux and identify the presence of parasitic currents due to the accumulation of charge in the readout electronics to cause the above-mentioned artifact in the detection efficiency. Our approach allows us to determine the maximum photon count rate at which the detector can be operated without adverse effects. Our findings are particularly important to avoid artifacts when applying SNSPDs for quantum tomography. We acknowledge support through ERC Consolidator Grant No. 724707 and from the Deutsche Forschungsgemeinschaft through Project No. PE 1832/5-1,2, as well as funding by the Volkswagen Foundation. This project has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant Agreement No. 675745. V.K. and G.G. acknowledge support from the Russian Science Foundation Project No. 16-12-00045 (NbN film deposition and testing). A.V. acknowledges support from the Karlsruhe School of Optics and Photonics (KSOP). |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1185 | |||
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Author | Polyakova, M.; Semenov, A. V.; Kovalyuk, V.; Ferrari, S.; Pernice, W. H. P.; Gol'tsman, G. N. | ||||
Title | Protocol of measuring hot-spot correlation length for SNSPDs with near-unity detection efficiency | Type | Journal Article | ||
Year | 2019 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 29 | Issue | 5 | Pages | 1-5 |
Keywords | SSPD, waveguide-integrated SNSPD, hot-spot interaction length | ||||
Abstract | We present a simple quantum detector tomography protocol, which allows, without ambiguities, to measure the two-spot detection efficiency and extract the hot-spot interaction length of superconducting nanowire single photon detectors (SNSPDs) with unity intrinsic detection efficiency. We identify a significant parasitic contribution to the measured two-spot efficiency, related to an effect of the bias circuit, and find a way to rule out this contribution during data post-processing and directly in the experiment. From the data analysis for waveguide-integrated SNSPD, we find signatures of the saturation of the two-spot efficiency and hot-spot interaction length of order of 100 nm. | ||||
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Language | Summary Language | Original Title | |||
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Series Volume | Series Issue | Edition | |||
ISSN | 1051-8223 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1187 | |||
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Author | Moshkova, M.; Divochiy, A.; Morozov, P.; Vakhtomin, Y.; Antipov, A.; Zolotov, P.; Seleznev, V.; Ahmetov, M.; Smirnov, K. | ||||
Title | High-performance superconducting photon-number-resolving detectors with 86% system efficiency at telecom range | Type | Journal Article | ||
Year | 2019 | Publication | J. Opt. Soc. Am. B | Abbreviated Journal | J. Opt. Soc. Am. B |
Volume | 36 | Issue | 3 | Pages | B20 |
Keywords | NbN PNR SSPD, SNSPD | ||||
Abstract | The use of improved fabrication technology, highly disordered NbN thin films, and intertwined section topology makes it possible to create high-performance photon-number-resolving superconducting single-photon detectors (PNR SSPDs) that are comparable to conventional single-element SSPDs at the telecom range. The developed four-section PNR SSPD has simultaneously an 86±3% system detection efficiency, 35 cps dark count rate, ∼2 ns dead time, and maximum 90 ps jitter. An investigation of the PNR SSPD’s detection efficiency for multiphoton events shows good uniformity across sections. As a result, such a PNR SSPD is a good candidate for retrieving the photon statistics for light sources and quantum key distribution systems. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 0740-3224 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1225 | |||
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Author | Rasulova, G. K.; Pentin, I. V.; Goltsman, G. N. | ||||
Title | Terahertz emission from a weakly-coupled GaAs/AlGaAs superlattice biased into three different modes of current self-oscillations | Type | Journal Article | ||
Year | 2019 | Publication | AIP Advances | Abbreviated Journal | AIP Advances |
Volume | 9 | Issue | 10 | Pages | 105220 |
Keywords | GaAs/AlGaAs superlattice, SL, NbN HEB | ||||
Abstract | Radio-frequency modulated terahertz (THz) emission power from weakly-coupled GaAs/AlGaAs superlattice (SL) has been increased by parallel connection of several SL mesas. Each SL mesa is a self-oscillator with its own oscillation frequency and mode. In coupled non-identical SL mesas biased at different voltages within the hysteresis loop the chaotic, quasiperiodic and frequency-locked modes of self-oscillations of current arise. THz emission was detected when three connected in parallel SL mesas were biased into the frequency-locked and quasiperiodic modes of self-oscillations of current, while in the chaotic mode of those it falls to the noise level. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 2158-3226 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1274 | |||
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Author | Elezov, M.; Ozhegov, R.; Goltsman, G.; Makarov, V. | ||||
Title | Countermeasure against bright-light attack on superconducting nanowire single-photon detector in quantum key distribution | Type | Journal Article | ||
Year | 2019 | Publication | Opt. Express | Abbreviated Journal | Opt. Express |
Volume | 27 | Issue | 21 | Pages | 30979-30988 |
Keywords | SSPD, SNSPD | ||||
Abstract | We present an active anti-latching system for superconducting nanowire single-photon detectors. We experimentally test it against a bright-light attack, previously used to compromise security of quantum key distribution. Although our system detects continuous blinding, the detector is shown to be partially blindable and controllable by specially tailored sequences of bright pulses. Improvements to the countermeasure are suggested. | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 1094-4087 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:31684339 | Approved | no | ||
Call Number | Serial | 1275 | |||
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Author | Antipov, S.; Trifonov, A.; Krause, S.; Meledin, D.; Kaurova, N.; Rudzinski, M.; Desmaris, V.; Belitsky, V.; Goltsman, G. | ||||
Title | Improved bandwidth of a 2 THz hot-electron bolometer heterodyne mixer fabricated on sapphire with a GaN buffer layer | Type | Journal Article | ||
Year | 2019 | Publication | Supercond. Sci. Technol. | Abbreviated Journal | Supercond. Sci. Technol. |
Volume | 32 | Issue | 7 | Pages | 075003 |
Keywords | NbN HEB mixer, GaN buffer layer, sapphire substrate | ||||
Abstract | We report on the signal-to-noise and gain bandwidth of a niobium nitride (NbN) hot-electron bolometer (HEB) mixer at 2 THz fabricated on a sapphire substrate with a GaN buffer layer. Two mixers with different DC properties and geometrical dimensions were studied and they demonstrated very close bandwidth performance. The signal-to-noise bandwidth is increased to 8 GHz in comparison to the previous results, obtained without a buffer-layer. The data were taken in a quasi-optical system with the use of the signal-to-noise method, which is close to the signal levels used in actual astrophysical observations. We find an increase of the gain bandwidth to 5 GHz. The results indicate that prior results obtained on a substrate of crystalline GaN can also be obtained on a conventional sapphire substrate with a few micron MOCVD-deposited GaN buffer-layer. | ||||
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Publisher | IOP Publishing | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
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Notes | Approved | no | |||
Call Number | Antipov_2019 | Serial | 1277 | ||
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Author | Nikogosyan, A. S.; Martirosyan, R. M.; Hakhoumian, A. A.; Makaryan, A. H.; Tadevosyan, V. R.; Goltsman, G. N.; Antipov, S. V. | ||||
Title | Effect of absorption on the efficiency of terahertz radiation generation in the metal waveguide partially filled with nonlinear crystal LiNbO3, DAST or ZnTe | Type | Journal Article | ||
Year | 2019 | Publication | J. Contemp. Phys. | Abbreviated Journal | J. Contemp. Phys. |
Volume | 54 | Issue | 1 | Pages | 97-104 |
Keywords | nonlinear crystal, THz, waveguide | ||||
Abstract | The influence of terahertz (THz) radiation absorption on the efficiency of generation of coherent THz radiation in the system ‘nonlinear-optical crystal partially filling the cross section of a rectangular metal waveguide’ has been investigated. The efficiency of the nonlinear frequency conversion of optical laser radiation to the THz range depends on the loss in the system and the fulfillment of the phase-matching (FM) condition in a nonlinear crystal. The method of partially filling of a metal waveguide with a nonlinear optical crystal is used to ensure phase matching. The phase matching is achieved by numerical determination of the thickness of the nonlinear crystal, that is the degree of partial filling of the waveguide. The attenuation of THz radiation caused by losses both in the metal walls of the waveguide and in the crystal was studied, taking into account the dimension of the cross section of the waveguide, the degree of partial filling, and the dielectric constant of the crystal. It is shown that the partial filling of the waveguide with a nonlinear crystal results in an increase in the efficiency of generation of THz radiation by an order of magnitude, owing to the decrease in absorption. | ||||
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Series Volume | Series Issue | Edition | |||
ISSN | 1068-3372 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1289 | |||
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Author | Ren, Y.; Zhang, D. X.; Zhou, K. M.; Miao, W.; Zhang, W.; Shi, S. C.; Seleznev, V.; Pentin, I.; Vakhtomin, Y.; Smirnov, K. | ||||
Title | 10.6 μm heterodyne receiver based on a superconducting hot-electron bolometer mixer and a quantum cascade laser | Type | Journal Article | ||
Year | 2019 | Publication | AIP Advances | Abbreviated Journal | AIP Advances |
Volume | 9 | Issue | 7 | Pages | 075307 |
Keywords | NbN HEB mixers, QCL, IR | ||||
Abstract | We report on the development of a heterodyne receiver at mid-infrared wavelength for high-resolution spectroscopy applications. The receiver employs a superconducting NbN hot electron bolometer as a mixer and a room temperature distributed feedback quantum cascade laser operating at 10.6 μm (28.2 THz) as a local oscillator. The stabilization of the heterodyne receiver has been achieved using a feedback loop controlling the output power of the laser. Improved Allan variance times as well as a double sideband receiver noise temperature of 5000 K and a noise bandwidth of 2.8 GHz of the receiver system are demonstrated. The work is supported in part by the National Key R&D Program of China under Grant 2018YFA0404701, by the CAS program under Grant QYZDJ-SSW-SLH043 and GJJSTD20180003, by the National Natural Science Foundation of China (NSFC) under Grant 11773083, by the “Hundred Talents Program” of the “Pioneer Initiative”, and in part by the CAS Key Lab for Radio Astronomy. |
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Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2158-3226 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1293 | |||
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