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Author | Gayduchenko, I. A.; Fedorov, G. E.; Moskotin, M. V.; Yagodkin, D. I.; Seliverstov, S. V.; Goltsman, G. N.; Yu Kuntsevich, A.; Rybin, M. G.; Obraztsova, E. D.; Leiman, V. G.; Shur, M. S.; Otsuji, T.; Ryzhii, V. I. | ||||
Title | Manifestation of plasmonic response in the detection of sub-terahertz radiation by graphene-based devices | Type | Journal Article | ||
Year | 2018 | Publication | Nanotechnol. | Abbreviated Journal | Nanotechnol. |
Volume | 29 | Issue | 24 | Pages | 245204 (1 to 8) |
Keywords | single layer graphene, graphene nanoribbons | ||||
Abstract | We report on the sub-terahertz (THz) (129-450 GHz) photoresponse of devices based on single layer graphene and graphene nanoribbons with asymmetric source and drain (vanadium and gold) contacts. Vanadium forms a barrier at the graphene interface, while gold forms an Ohmic contact. We find that at low temperatures (77 K) the detector responsivity rises with the increasing frequency of the incident sub-THz radiation. We interpret this result as a manifestation of a plasmonic effect in the devices with the relatively long plasmonic wavelengths. Graphene nanoribbon devices display a similar pattern, albeit with a lower responsivity. | ||||
Address | Physics Department, Moscow State University of Education, Moscow 119991, Russia. National Research Center 'Kurchatov Institute', 123182, Moscow, Russia | ||||
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ISSN | 0957-4484 | ISBN | Medium | ||
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Notes | PMID:29553479 | Approved | no | ||
Call Number | Serial | 1308 | |||
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Author | Bandurin, D. A.; Gayduchenko, I.; Cao, Y.; Moskotin, M.; Principi, A.; Grigorieva, I. V.; Goltsman, G.; Fedorov, G.; Svintsov, D. | ||||
Title | Dual origin of room temperature sub-terahertz photoresponse in graphene field effect transistors | Type | Journal Article | ||
Year | 2018 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 112 | Issue | 14 | Pages | 141101 (1 to 5) |
Keywords | graphene field effect transistors, FET | ||||
Abstract | Graphene is considered as a promising platform for detectors of high-frequency radiation up to the terahertz (THz) range due to its superior electron mobility. Previously, it has been shown that graphene field effect transistors (FETs) exhibit room temperature broadband photoresponse to incoming THz radiation, thanks to the thermoelectric and/or plasma wave rectification. Both effects exhibit similar functional dependences on the gate voltage, and therefore, it was difficult to disentangle these contributions in previous studies. In this letter, we report on combined experimental and theoretical studies of sub-THz response in graphene field-effect transistors analyzed at different temperatures. This temperature-dependent study allowed us to reveal the role of the photo-thermoelectric effect, p-n junction rectification, and plasmonic rectification in the sub-THz photoresponse of graphene FETs. D.A.B. acknowledges the Leverhulme Trust for financial support. The work of D.S. was supported by Grant No. 16-19-10557 of the Russian Scientific Foundation (theoretical model). G.F., I.G., M.M., and G.G. acknowledge the Russian Science Foundation [Grant No. 14-19-01308 (MIET, cryostat upgrade) and Grant No. 17-72-30036, (MSPU, photoresponse measurements), the Ministry of Education and Science of the Russian Federation (Contract No. 14.B25.31.0007 (device fabrication) and Task No. 3.7328.2017/LS (NEP analyses)] and the Russian Foundation for Basic Research [Grant No. 15-02-07841 (device design)]. The authors are grateful to Professor M. S. Shur for helpful discussions. |
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ISSN | 0003-6951 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1309 | |||
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Author | Florya, I. N.; Korneeva, Y. P.; Mikhailov, M. Y.; Devizenko, A. Y.; Korneev, A. A.; Goltsman, G. N. | ||||
Title | Photon counting statistics of superconducting single-photon detectors made of a three-layer WSi film | Type | Journal Article | ||
Year | 2018 | Publication | Low Temp. Phys. | Abbreviated Journal | Low Temp. Phys. |
Volume | 44 | Issue | 3 | Pages | 221-225 |
Keywords | WSi SSPD, SNSPD | ||||
Abstract | Superconducting nanowire single-photon detectors (SNSPD) are used in quantum optics when record-breaking time resolution, high speed, and exceptionally low levels of dark counts (false readings) are required. Their detection efficiency is limited, however, by the absorption coefficient of the ultrathin superconducting film for the detected radiation. One possible way of increasing the detector absorption without limiting its broadband response is to make a detector in the form of several vertically stacked layers and connect them in parallel. For the first time we have studied single-photon detection in a multilayer structure consisting of three superconducting layers of amorphous tungsten silicide (WSi) separated by thin layers of amorphous silicon. Two operating modes of the detector are illustrated: an avalanche regime and an arm-trigger regime. A shift in these modes occurs at currents of ∼0.5–0.6 times the critical current of the detector. This work was supported by technical task No. 88 for scientific research at the National Research University “Higher School of Economics,” Grant No. 14.V25.31.0007 from the Ministry of Education and Science of Russia, and the work of G. N. Goltsman was supported by task No. 3.7328.2017/VU of the Ministry of Education and Science of Russia. |
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ISSN | 1063-777X | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1310 | |||
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Author | Iomdina, E. N.; Seliverstov, S. V.; Sianosyan, A. A.; Teplyakova, K. O.; Rusova, A. A.; Goltsman, G. N. | ||||
Title | Terahertz scanning for evaluation of corneal and scleral hydration | Type | Journal Article | ||
Year | 2018 | Publication | Sovremennye tehnologii v medicine | Abbreviated Journal | STM |
Volume | 10 | Issue | 4 | Pages | 143-149 |
Keywords | BWO; Golay cell; medicine; cornea; sclera; THz radiation; corneal hydration; backward-wave oscillator; avalanche transit-time diode; IMPATT diode | ||||
Abstract | The aim of the investigation was to study the prospects of using continuous THz scanning of the cornea and the sclera to determine water concentration in these tissues and on the basis of the obtained data to develop the experimental installation for monitoring corneal and scleral hydration degree.Materials and Methods. To evaluate corneal and scleral transmittance and reflectance spectra in the THz range, the developed experimental installations were used to study 3 rabbit corneas and 3 scleras, 2 whole rabbit eyes, and 3 human scleras. Besides, two rabbit eyes were studied in vivo prior to keratorefractive surgery as well as 10 and 21 days following the surgery (LASIK).Results. There have been created novel experimental installations enabling in vitro evaluation of frequency dependence of corneal and scleral transmittance coefficients and reflectance coefficients on water percentage in the THz range. Decrease in corneal water content by 1% was found to lead to reliably established decrease in the reflected signal by 13%. The reflectance spectrum of the whole rabbit eye was measured in the range of 0.13–0.32 THz. The study revealed the differences between the indices of rabbit cornea and sclera, as well as rabbit and human sclera. There was developed a laboratory model of the installation for in vivo evaluation of corneal and scleral hydration using THz radiation.Conclusion. The preliminary findings show that the proposed technique based on the use of continuous THz radiation can be employed to create a device for noninvasive control of corneal and scleral hydration. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1315 | |||
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Author | Fedorov, G.; Gayduchenko, I.; Titova, N.; Gazaliev, A.; Moskotin, M.; Kaurova, N.; Voronov, B.; Goltsman, G. | ||||
Title | Carbon nanotube based schottky diodes as uncooled terahertz radiation detectors | Type | Journal Article | ||
Year | 2018 | Publication | Phys. Status Solidi B | Abbreviated Journal | Phys. Status Solidi B |
Volume | 255 | Issue | 1 | Pages | 1700227 (1 to 6) |
Keywords | carbon nanotube schottky diodes, CNT | ||||
Abstract | Despite the intensive development of the terahertz technologies in the last decade, there is still a shortage of efficient room‐temperature radiation detectors. Carbon nanotubes (CNTs) are considered as a very promising material possessing many of the features peculiar for graphene (suppression of backscattering, high mobility, etc.) combined with a bandgap in the carrier spectrum. In this paper, we investigate the possibility to incorporate individual CNTs into devices that are similar to Schottky diodes. The latter is currently used to detect radiation with a frequency up to 50 GHz. We report results obtained with semiconducting (bandgap of about 0.5 eV) and quasi‐metallic (bandgap of few meV) single‐walled carbon nanotubes (SWNTs). Semiconducting CNTs show better performance up to 300 GHz with responsivity up to 100 V W−1, while quasi‐metallic CNTs are shown to operate up to 2.5 THz. | ||||
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ISSN | 0370-1972 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1321 | |||
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Author | Seliverstov, S. V.; Anfertyev, V. A.; Tretyakov, I. V.; Ozheredov, I. A.; Solyankin, P. M.; Revin, L. S.; Vaks, V. L.; Rusova, A. A.; Goltsman, G. N.; Shkurinov, A. P. | ||||
Title | Terahertz heterodyne receiver with an electron-heating mixer and a heterodyne based on the quantum-cascade laser | Type | Journal Article | ||
Year | 2017 | Publication | Radiophys. Quant. Electron. | Abbreviated Journal | Radiophys. Quant. Electron. |
Volume | 60 | Issue | 7 | Pages | 518-524 |
Keywords | NbN HEB mixer, QCL | ||||
Abstract | We study characteristics of the laboratory prototype of a terahertz heterodyne receiver with an electron-heating mixer and a heterodyne based on the quantum-cascade laser. The results obtained demonstrate the possibility to use this receiver as a basis for creation of a high-sensitivity terahertz spectrometer, which can be used in many basic and practical applications. A significant advantage of this receiver will be the possibility of placing the mixer and heterodyne in the same cryostat, which will reduce the device dimensions considerably. The obtained experimental results are analyzed, and methods of optimizing the parameters of the receiver are proposed. | ||||
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ISSN | 0033-8443 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1322 | |||
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Author | Trifonov, A.; Tong, C.-Y. E.; Grimes, P.; Lobanov, Y.; Kaurova, N.; Blundell, R.; Goltsman, G. | ||||
Title | Development of a silicon membrane-based multipixel hot electron bolometer receiver | Type | Journal Article | ||
Year | 2017 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 27 | Issue | 4 | Pages | 1-5 |
Keywords | Multi-pixel, NbN HEB, silicon-on-insulator, horn array | ||||
Abstract | We report on the development of a multipixel hot electron bolometer (HEB) receiver fabricated using silicon membrane technology. The receiver comprises a 2 × 2 array of four HEB mixers, fabricated on a single chip. The HEB mixer chip is based on a superconducting NbN thin-film deposited on top of the silicon-on-insulator (SOI) substrate. The thicknesses of the device layer and handling layer of the SOI substrate are 20 and 300 μm, respectively. The thickness of the device layer is chosen such that it corresponds to a quarter-wave in silicon at 1.35 THz. The HEB mixer is integrated with a bow-tie antenna structure, in turn designed for coupling to a circular waveguide, fed by a monolithic drilled smooth-walled horn array. | ||||
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ISSN | 1051-8223 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1324 | |||
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Author | Korneeva, Y.; Florya, I.; Vdovichev, S.; Moshkova, M.; Simonov, N.; Kaurova, N.; Korneev, A.; Goltsman, G. | ||||
Title | Comparison of hot spot formation in nbn and mon thin superconducting films after photon absorption | Type | Journal Article | ||
Year | 2017 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 27 | Issue | 4 | Pages | 1-4 |
Keywords | MoNx SSPD | ||||
Abstract | In superconducting single-photon detectors (SSPD), the efficiency of local suppression of superconductivity and hotspot formation is controlled by diffusivity and electron-phonon interaction time. Here, we selected a material, 3.6-nm-thick MoNx film, which features diffusivity close to those of NbN traditionally used for SSPD fabrication, but with electron-phonon interaction time an order of magnitude larger. In MoN ∞ detectors, we study the dependence of detection efficiency on bias current, photon energy, and strip width, and compare it with NbN SSPD. We observe nonlinear current-energy dependence in MoNx SSPD and more pronounced plateaus in dependences of detection efficiency on bias current, which we attribute to longer electron-phonon interaction time. | ||||
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ISSN | 1051-8223 | ISBN | Medium | ||
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Notes | Approved | no | |||
Call Number | Serial | 1325 | |||
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Author | Trifonov, A.; Tong, C.-Y. E.; Lobanov, Y.; Kaurova, N.; Blundell, R.; Goltsman, G. | ||||
Title | Photon absorption near the gap frequency in a hot electron bolometer | Type | Journal Article | ||
Year | 2017 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 27 | Issue | 4 | Pages | 1-4 |
Keywords | NBN HEB mixer | ||||
Abstract | The superconducting energy gap is a fundamental characteristic of a superconducting film, which, together with the applied pump power and the biasing setup, defines the instantaneous resistive state of the Hot Electron Bolometer (HEB) mixer at any given bias point on the I-V curve. In this paper we report on a series of experiments, in which we subjected the HEB to radiation over a wide frequency range along with parallel microwave injection. We have observed three distinct regimes of operation of the HEB, depending on whether the radiation is above the gap frequency, far below it or close to it. These regimes are driven by the different patterns of photon absorption. The experiments have allowed us to derive the approximate gap frequency of the device under test as about 585 GHz. Microwave injection was used to probe the HEB impedance. Spontaneous switching between the superconducting (low resistive) state and a quasi-normal (high resistive) state was observed. The switching pattern depends on the particular regime of HEB operation and can assume a random pattern at pump frequencies below the gap to a regular relaxation oscillation running at a few MHz when pumped above the gap. | ||||
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ISSN | 1558-2515 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 1331 | |||
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Author | Iomdina, E. N.; Goltsman, G. N.; Seliverstov, S. V.; Sianosyan, A. A.; Teplyakova, K. O.; Rusova, A. A. | ||||
Title | Study of transmittance and reflectance spectra of the cornea and the sclera in the THz frequency range | Type | Journal Article | ||
Year | 2016 | Publication | J. Biomed. Opt. | Abbreviated Journal | J. Biomed. Opt. |
Volume | 21 | Issue | 9 | Pages | 97002 (1 to 5) |
Keywords | BWO, IMPATT diode, Schottky diode, medicine, animals, cornea, physiology, humans, rabbits, sclera diagnostic imaging, physiology | ||||
Abstract | An adequate water balance (hydration extent) is one of the basic factors of normal eye function, including its external shells: the cornea and the sclera. Adequate control of corneal and scleral hydration is very important for early diagnosis of a variety of eye diseases, stating indications for and contraindications against keratorefractive surgeries and the choice of contact lens correction solutions. THz systems of creating images in reflected beams are likely to become ideal instruments of noninvasive control of corneal and scleral hydration degrees. This paper reports on the results of a study involving transmittance and reflectance spectra for the cornea and the sclera of rabbit and human eyes, as well as those of the rabbit eye, in the frequency range of 0.13 to 0.32 THz. The dependence of the reflectance coefficient of these tissues on water mass percentage content was determined. The experiments were performed on three corneas, three rabbit scleras, two rabbit eyes, and three human scleras. The preliminary results demonstrate that the proposed technique, based on the use of a continuous THz radiation, may be utilized to create a device for noninvasive control of corneal and scleral hydration, which has clear potential of broad practical application. | ||||
Address | Moscow State Pedagogical University, Department of Physics, 29 Malaya Pirogovskaya Street, Moscow 119435, Russia | ||||
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Language | English | Summary Language | Original Title | ||
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ISSN | 1083-3668 | ISBN | Medium | ||
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Notes | PMID:27626901 | Approved | no | ||
Call Number | Serial | 1335 | |||
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