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Author Samsonova, Alena; Zolotov, Philipp; Baeva, Elmira; Lomakin, Andrey; Titova, Nadezhda; Kardakova, Anna; Goltsman, Gregory
Title (up) Signatures of surface magnetic disorder in thin niobium films Type Journal Article
Year 2021 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal
Volume Issue Pages 1-1
Keywords Temperature measurement, Temperature dependence, Superconducting magnets, Superconducting transition temperature, Substrates, Resistance, Scattering
Abstract We present our studies on the evolution of the normal and superconducting properties with thickness of thin Nb films with a low level of non-magnetic disorder (kFl 150 for the thickest film in the set). The analysis of the superconducting behavior points to the presence of magnetic moments, hidden in the native oxide on the surface of Nb films. Using the Abrikosov-Gorkov theory, we obtain the density of surface magnetic moments of 1013 cm-2, which is in agreement with the previously reported data for Nb films.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1162
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Author Baksheeva, K.; Vdovydchenko, A.; Gorshkov, K.; Ozhegov, R.; Kinev, N.; Koshelets, V.; Goltsman, G.
Title (up) Study of human skin radiation in the terahertz frequency range Type Conference Article
Year 2019 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1410 Issue Pages 012076 (1 to 5)
Keywords SIS mixer, SIR, applications, medicine, sympathetic nervous system, SNS
Abstract The radiation of human skin in the terahertz frequency range under the influence of mental stresses has been studied in the current work. An experimental setup for observation of changes in human skin radiation, which occur under the influence of psychological stresses, by means of a superconducting integrated receiver has been developed. More than 30 volunteers participate in these studies, which allows us to verify presence of correlation between the signals from the superconducting integrated terahertz receiver and other sensors that monitor human mental stress.
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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 1272
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Author Shein, K. V.; Zarudneva, A. A.; Emel’yanova, V. O.; Logunova, M. A.; Chichkov, V. I.; Sobolev, A.S.; Zav’yalov, V. V.; Lehtinen, J. S.; Smirnov, E. O.; Korneeva, Y. P.; Korneev, A. A.; Arutyunov, K. Y.
Title (up) Superconducting microstructures with high impedance Type Journal Article
Year 2020 Publication Phys. Solid State Abbreviated Journal Phys. Solid State
Volume 62 Issue 9 Pages 1539-1542
Keywords superconducting channels, SIS, inetic inductance, tunneling contacts, high impedance
Abstract The transport properties of two types of quasi-one-dimensional superconducting microstructures were investigated at ultra-low temperatures: the narrow channels close-packed in the shape of meander, and the chains of tunneling contacts “superconductor-insulator-superconductor.” Both types of the microstructures demonstrated high value of high-frequency impedance and-or the dynamic resistance. The study opens up potential for using of such structures as current stabilizing elements with zero dissipation.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-7834 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1789
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Author Ozhegov, R. V.; Gorshkov, K. N.; Vachtomin, Y. B.; Smirnov, K. V.; Finkel, M. I.; Goltsman, G. N.; Kiselev, O. S.; Kinev, N. V.; Filippenko, L. V.; Koshelets, V. P.
Title (up) Terahertz imaging system based on superconducting heterodyne integrated receiver Type Conference Article
Year 2014 Publication Proc. THz and Security Applications Abbreviated Journal Proc. THz and Security Applications
Volume Issue Pages 113-125
Keywords SIS mixer, SIR, THz imaging
Abstract The development of terahertz imaging instruments for security systems is on the cutting edge of terahertz technology. We are developing a THz imaging system based on a superconducting integrated receiver (SIR). An SIR is a new type of heterodyne receiver based on an SIS mixer integrated with a flux-flow oscillator (FFO) and a harmonic mixer which is used for phase-locking the FFO. Employing an SIR in an imaging system means building an entirely new instrument with many advantages compared to traditional systems.

In this project we propose a prototype THz imaging system using an 1 pixel SIR and 2D scanner. At a local oscillator frequency of 500 GHz the best noise equivalent temperature difference (NETD) of the SIR is 10 mK at an integration time of 1 s and a detection bandwidth of 4 GHz. The scanner consists of two rotating flat mirrors placed in front of the antenna consisting of a spherical primary reflector and an aspherical secondary reflector. The diameter of the primary reflector is 0.3 m. The operating frequency of the imaging system is 600 GHz, the frame rate is 0.1 FPS, the scanning area is 0.5 × 0.5 m2, the image resolution is 50 × 50 pixels, the distance from an object to the scanner was 3 m. We have obtained THz images with a spatial resolution of 8 mm and a NETD of less than 2 K.
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Corporate Author Thesis
Publisher Springer Netherlands Place of Publication Dordrecht Editor Corsi, C.; Sizov, F.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-94-017-8828-1 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1368
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Author Ozhegov, R. V.; Gorshkov, K. N.; Smirnov, K. V.; Gol’tsman, G. N.; Filippenko, L. V.; Koshelets, V. P.
Title (up) Terahertz imaging system based on superconducting integrated receiver Type Conference Article
Year 2010 Publication Proc. 2-nd Int. Conf. Terahertz and Microwave radiation: Generation, Detection and Applications Abbreviated Journal Proc. 2-nd Int. Conf. Terahertz and Microwave radiation: Generation, Detection and Applications
Volume Issue Pages 20-22
Keywords SIS mixer, SIR
Abstract The development of terahertz imaging instruments for security systems is on the cutting edge of terahertz technology. We are developing a THz imaging system based on a superconducting integrated receiver (SIR). An SIR is a new type of heterodyne receiver based on an SIS mixer integrated with a flux-flow oscillator (FFO) and a harmonic mixer which is used for phase-locking the FFO. Developing an array of SIRs would allow obtaining amplitude and phase characteristics of incident radiation in the plane of the receiver. Employing an SIR in an imaging system means building an entirely new instrument with many advantages compare to traditional systems: i) high temperature resolution, comparable to the best results for incoherent receivers; ii) high spectral resolution allowing spectral analysis of various substances; iii) the local oscillator frequency can be varied to obtain images at different frequencies, effectively providing “color” images; iv) since a heterodyne receiver preserves the phase of the radiation, it is possible to construct 3D images. The paper presents a prototype THz imaging system using an 1 pixel SIR. We have studied the dependence of the noise equivalent temperature difference (NETD) on the integration time and also possible ways of achieving best possible sensitivity. An NETD of 13 mK was obtained with an integration time of 1 sec a detection bandwidth of 4 GHz at a local oscillator frequency of 520 GHz. An important advantage of an FFO is its wide operation range: 300-700 GHz.
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Notes Approved no
Call Number ozhegov2010terahertz Serial 1397
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Author Gayduchenko, I. A.; Moskotin, M. V.; Matyushkin, Y. E.; Rybin, M. G.; Obraztsova, E. D.; Ryzhii, V. I.; Goltsman, G. N.; Fedorov, G. E.
Title (up) The detection of sub-terahertz radiation using graphene-layer and graphene-nanoribbon FETs with asymmetric contacts Type Conference Article
Year 2018 Publication Materials Today: Proc. Abbreviated Journal Materials Today: Proc.
Volume 5 Issue 13 Pages 27301-27306
Keywords graphene nanoribbons, graphene-nanoribbon, GNR FET, field effect transistor
Abstract We report on the detection of sub-terahertz radiation using single layer graphene and graphene-nanoribbon FETs with asymmetric contacts (one is the Schottky contact and one – the Ohmic contact). We found that cutting graphene into ribbons a hundred nanometers wide leads to a decrease of the response to sub-THz radiation. We show that suppression of the response in the graphene nanoribbons devices can be explained by unusual properties of the Schottky barrier on graphene-vanadium interface.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2214-7853 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1316
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Author Ozhegov, R. V.; Gorshkov, K. N.; Gol'tsman, G. N.; Kinev, N. V.; Koshelets, V. P.
Title (up) The stability of a terahertz receiver based on a superconducting integrated receiver Type Journal Article
Year 2011 Publication Supercond. Sci. Technol. Abbreviated Journal Supercond. Sci. Technol.
Volume 24 Issue 3 Pages 035003
Keywords SIS mixer, SIR, stability
Abstract We present the results of stability testing of a terahertz radiometer based on a superconducting receiver with a SIS tunnel junction as the mixer and a flux-flow oscillator as the local oscillator. In the continuum mode, the receiver with a noise temperature of 95 K at 510 GHz measured over the intermediate frequency (IF) passband of 4-8 GHz offered a noise equivalent temperature difference of 10 ± 1 mK at an integration time of 1 s. We offer a method to significantly increase the integration time without the use of complex measurement equipment. The receiver observed a strong signal over a final detection bandwidth of 4 GHz and offered an Allan time of 5 s.
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Notes Approved no
Call Number RPLAB @ gujma @ Serial 705
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Author Gayduchenko, I.; Fedorov, G.; Titova, N.; Moskotin, M.; Obraztsova, E.; Rybin, M.; Goltsman, G.
Title (up) Towards to the development of THz detectors based on carbon nanostructures Type Conference Article
Year 2018 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1092 Issue Pages 012039 (1 to 4)
Keywords CVD graphene, carbon nanotubes, CNT, field effect transistors, FET, THz detectors
Abstract Demand for efficient terahertz radiation detectors resulted in intensive study of the carbon nanostructures as possible solution for that problem. In this work we investigate the response to sub-terahertz radiation of detectors with sensor elements based on CVD graphene as well as its derivatives – carbon nanotubes (CNTs). The devices are made in configuration of field effect transistors (FET) with asymmetric source and drain (vanadium and gold) contacts and operate as lateral Schottky diodes. We show that at 300K semiconducting CNTs show better performance up to 300GHz with responsivity up to 100V/W, while quasi-metallic CNTs are shown to operate up to 2.5THz. At 300 K graphene detector exhibit the room-temperature responsivity from R = 15 V/W at f = 129 GHz to R = 3 V/W at f = 450 GHz. We find that at low temperatures (77K) the graphene lateral Schottky diodes 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. The obtained data allows for determination of the most promising directions of development of the technology of nanocarbon structures for the detection of THz radiation.
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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 1302
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Author Gayduchenko, I.; Xu, S. G.; Alymov, G.; Moskotin, M.; Tretyakov, I.; Taniguchi, T.; Watanabe, K.; Goltsman, G.; Geim, A. K.; Fedorov, G.; Svintsov, D.; Bandurin, D. A.
Title (up) Tunnel field-effect transistors for sensitive terahertz detection Type Journal Article
Year 2021 Publication Nat. Commun. Abbreviated Journal Nat. Commun.
Volume 12 Issue 1 Pages 543
Keywords field-effect transistors, bilayer graphene, BLG
Abstract The rectification of electromagnetic waves to direct currents is a crucial process for energy harvesting, beyond-5G wireless communications, ultra-fast science, and observational astronomy. As the radiation frequency is raised to the sub-terahertz (THz) domain, ac-to-dc conversion by conventional electronics becomes challenging and requires alternative rectification protocols. Here, we address this challenge by tunnel field-effect transistors made of bilayer graphene (BLG). Taking advantage of BLG's electrically tunable band structure, we create a lateral tunnel junction and couple it to an antenna exposed to THz radiation. The incoming radiation is then down-converted by the tunnel junction nonlinearity, resulting in high responsivity (>4 kV/W) and low-noise (0.2 pW/[Formula: see text]) detection. We demonstrate how switching from intraband Ohmic to interband tunneling regime can raise detectors' responsivity by few orders of magnitude, in agreement with the developed theory. Our work demonstrates a potential application of tunnel transistors for THz detection and reveals BLG as a promising platform therefor.
Address Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA. bandurin@mit.edu
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 2041-1723 ISBN Medium
Area Expedition Conference
Notes PMID:33483488; PMCID:PMC7822863 Approved no
Call Number Serial 1261
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Author Dube, I.; Jiménez, D.; Fedorov, G.; Boyd, A.; Gayduchenko, I.; Paranjape, M.; Barbara, P.
Title (up) Understanding the electrical response and sensing mechanism of carbon-nanotube-based gas sensors Type Journal Article
Year 2015 Publication Carbon Abbreviated Journal Carbon
Volume 87 Issue Pages 330-337
Keywords carbon nanotubes, CNT detectors, field effect transistors, FET
Abstract Gas sensors based on carbon nanotube field effect transistors (CNFETs) have outstanding sensitivity compared to existing technologies. However, the lack of understanding of the sensing mechanism has greatly hindered progress on calibration standards and customization of these nano-sensors. Calibration requires identifying fundamental transistor parameters and establishing how they vary in the presence of a gas. This work focuses on modeling the electrical response of CNTFETs in the presence of oxidizing (NO2) and reducing (NH3) gases and determining how the transistor characteristics are affected by gas-induced changes of contact properties, such as the Schottky barrier height and width, and by the doping level of the nanotube. From the theoretical fits of the experimental transfer characteristics at different concentrations of NO2 and NH3, we find that the CNTFET response can be modeled by introducing changes in the Schottky barrier height. These changes are directly related to the changes in the metal work function of the electrodes that we determine experimentally, independently, with a Kelvin probe. Our analysis yields a direct correlation between the ON – current and the changes in the electrode metal work function. Doping due to molecules adsorbed at the carbon-nanotube/metal interface also affects the transfer characteristics.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1778
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