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	Author	Arutyunov, K. Y.; Ramos-Alvarez, A.; Semenov, A. V.; Korneeva, Y. P.; An, P. P.; Korneev, A. A.; Murphy, A.; Bezryadin, A.; Gol'tsman, G. N.
	Title	Superconductivity in highly disordered NbN nanowires			Type	Journal Article
	Year	2016	Publication	Nanotechnol.	Abbreviated Journal	Nanotechnol.
	Volume	27	Issue	47	Pages	47lt02 (1 to 8)
	Keywords	NbN nanowires
	Abstract	The topic of superconductivity in strongly disordered materials has attracted significant attention. These materials appear to be rather promising for fabrication of various nanoscale devices such as bolometers and transition edge sensors of electromagnetic radiation. The vividly debated subject of intrinsic spatial inhomogeneity responsible for the non-Bardeen-Cooper-Schrieffer relation between the superconducting gap and the pairing potential is crucial both for understanding the fundamental issues of superconductivity in highly disordered superconductors, and for the operation of corresponding nanoelectronic devices. Here we report an experimental study of the electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. The temperature dependence of the critical current follows the textbook Ginzburg-Landau prediction for the quasi-one-dimensional superconducting channel I c approximately (1-T/T c)(3/2). We find that conventional models based on the the phase slip mechanism provide reasonable fits for the shape of R(T) transitions. Better agreement with R(T) data can be achieved assuming the existence of short 'weak links' with slightly reduced local critical temperature T c. Hence, one may conclude that an 'exotic' intrinsic electronic inhomogeneity either does not exist in our structures, or, if it does exist, it does not affect their resistive state properties, or does not provide any specific impact distinguishable from conventional weak links.
	Address	National Research University Higher School of Economics, Moscow Institute of Electronics and Mathematics,109028, Moscow, Russia. P L Kapitza Institute for Physical Problems RAS, Moscow, 119334, Russia
	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	0957-4484	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:27782000			Approved	no
	Call Number				Serial	1332
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	Author	Arutyunov, K. Y.; Ramos-Álvarez, A.; Semenov, A. V.; Korneeva, Y. P.; An, P. P.; Korneev, A. A.; Murphy, A.; Bezryadin, A.; Gol’tsman, G. N.
	Title	Quasi-1-dimensional superconductivity in highly disordered NbN nanowires			Type	Miscellaneous
	Year	2016	Publication	arXiv	Abbreviated Journal
	Volume		Issue		Pages
	Keywords	narrow NbN nanowires, BCS
	Abstract	The topic of superconductivity in strongly disordered materials has attracted a significant attention. In particular vivid debates are related to the subject of intrinsic spatial inhomogeneity responsible for non-BCS relation between the superconducting gap and the pairing potential. Here we report experimental study of electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. We find that conventional models based on phase slip concept provide reasonable fits for the shape of the R(T) transition curve. Temperature dependence of the critical current follows the text-book Ginzburg-Landau prediction for quasi-one-dimensional superconducting channel Ic~(1-T/Tc)^3/2. Hence, one may conclude that the intrinsic electronic inhomogeneity either does not exist in our structures, or, if exist, does not affect their resistive state properties.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes	Duplicated as 1332			Approved	no
	Call Number				Serial	1338
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	Author	Beebe, M. R.; Beringer, D. B.; Burton, M. C.; Yang, K.; Lukaszew, R. A.
	Title	Stoichiometry and thickness dependence of superconducting properties of niobium nitride thin films			Type	Journal Article
	Year	2016	Publication	Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films	Abbreviated Journal	Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films
	Volume	34	Issue	2	Pages	021510 (1 to 4)
	Keywords	potential plagiarism, possible plagiarism, NbN films
	Abstract	The current technology used in linear particle accelerators is based on superconducting radio frequency (SRF) cavities fabricated from bulk niobium (Nb), which have smaller surface resistance and therefore dissipate less energy than traditional nonsuperconducting copper cavities. Using bulk Nb for the cavities has several advantages, which are discussed elsewhere; however, such SRF cavities have a material-dependent accelerating gradient limit. In order to overcome this fundamental limit, a multilayered coating has been proposed using layers of insulating and superconducting material applied to the interior surface of the cavity. The key to this multilayered model is to use superconducting thin films to exploit the potential field enhancement when these films are thinner than their London penetration depth. Such field enhancement has been demonstrated in MgB2 thin films; here, the authors consider films of another type-II superconductor, niobium nitride (NbN). The authors present their work correlating stoichiometry and superconducting properties in NbN thin films and discuss the thickness dependence of their superconducting properties, which is important for their potential use in the proposed multilayer structure. While there are some previous studies on the relationship between stoichiometry and critical temperature TC, the authors are the first to report on the correlation between stoichiometry and the lower critical field HC1.
	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	0734-2101	ISBN		Medium
	Area		Expedition		Conference
	Notes	Potential plagiarism for 1503			Approved	no
	Call Number				Serial	1504
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	Author	Fedorov, G. E.; Stepanova, T. S.; Gazaliev, A. S.; Gaiduchenko, I. A.; Kaurova, N. S.; Voronov, B. M.; Goltzman, G. N.
	Title	Asymmetric devices based on carbon nanotubes for terahertz-range radiation detection			Type	Journal Article
	Year	2016	Publication	Semicond.	Abbreviated Journal	Semicond.
	Volume	50	Issue	12	Pages	1600-1603
	Keywords	carbon nanotubes, CNT detectors
	Abstract	Various asymmetric detecting devices based on carbon nanotubes (CNTs) are studied. The asymmetry is understood as inhomogeneous properties along the conducting channel. In the first type of devices, an inhomogeneous morphology of the CNT grid is used. In the second type of devices, metals with highly varying work functions are used as the contact material. The relation between the sensitivity and detector configuration is analyzed. Based on the data obtained, approaches to the development of an efficient detector of terahertz radiation, based on carbon nanotubes are proposed.
	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	1063-7826	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1776
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	Author	Finkel, M.; Thierschmann, H. R.; Galatro, L.; Katan, A. J.; Thoen, D. J.; de Visser, P. J.; Spirito, M.; Klapwijk, T. M.
	Title	Branchline and directional THz coupler based on PECVD SiNx-technology			Type	Conference Article
	Year	2016	Publication	41st IRMMW-THz	Abbreviated Journal	41st IRMMW-THz
	Volume		Issue		Pages
	Keywords	microstrip, fixtures, coplanar waveguides, couplers, standards, probes, dielectrics
	Abstract	A fabrication technology to realize THz microstrip lines and passive circuit components is developed and tested making use of a plasma-enhanced chemical vapor deposition grown silicon nitride (PECVD SiNx) dielectric membrane. We use 2 μm thick SiNx and 300 nm thick gold layers on sapphire substrates. We fabricate a set of structures for thru-reflect-line (TRL) calibration, with the reflection standard implemented as a short through the via. We find losses of 9.5 dB/mm at 300 GHz for a 50 Ohm line. For a branchline coupler we measure 2.5 dB insertion loss, 1 dB amplitude imbalance and 21 dB isolation. Good control over the THz lines parameters is proven by similar performance of a set of 5 structures. The directional couplers show -14 dB transmission to the coupled port, -24 dB to the isolated port and -25 dB in reflection. The SiNx membrane, used as a dielectric, is compatible with atomic force microscopy (AFM) cantilevers allowing the application of this technology to the development of a THz near-field microscope.
	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	2162-2035	ISBN	978-1-4673-8485-8	Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	7758586			Serial	1295
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	Author	Gayduchenko, I. A.; Fedorov, G. E.; Ibragimov, R. A.; Stepanova, T. S.; Gazaliev, A. S.; Vysochanskiy, N. A.; Bobrov, Y. A.; Malovichko, A. M.; Sosnin, I. M.; Bobrinetskiy, I. I.
	Title	Synthesis of single-walled carbon nanotube networks using monodisperse metallic nanocatalysts encapsulated in reverse micelles			Type	Journal Article
	Year	2016	Publication	Chem. Ind. Belgrade	Abbreviated Journal	Chem. Ind. Belgrade
	Volume	70	Issue	1	Pages	1-8
	Keywords	carbon nanotubes, CNT, reverse micelles
	Abstract	We report on a method of synthesis of single-walled carbon nanotubes percolated networks on silicon dioxide substrates using monodisperse Co and Ni catalyst. The catalytic nanoparticles were obtained by modified method of reverse micelles of bis-(2-ethylhexyl) sulfosuccinate sodium in isooctane solution that provides the nanoparticle size control in range of 1 to 5 nm. The metallic nanoparticles of Ni and Co were characterized using transmission electron microscopy (TEM) and atomic-force microscopy (AFM). Carbon nanotubes were synthesized by chemical vapor deposition of CH4/H2 composition at temperature 1000 °С on catalysts pre-deposited on silicon dioxide substrate. Before temperature treatment during the carbon nanotube synthesis most of the catalyst material agglomerates due to magnetic forces while during the nanotube growth disintegrates into the separate nanoparticles with narrow diameter distribution. The formed nanotube networks were characterized using AFM, scanning electron microscopy (SEM) and Raman spectroscopy. We find that the nanotubes are mainly single-walled carbon nanotubes with high structural perfection up to 200 μm long with diameters from 1.3 to 1.7 nm consistent with catalyst nanoparticles diameter distribution and independent of its 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	0367-598X	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1779
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	Author	Gayduchenko, I. A.; Fedorov, G. E.; Stepanova, T. S.; Titova, N.; Voronov, B. M.; But, D.; Coquillat, D.; Diakonova, N.; Knap, W.; Goltsman, G. N.
	Title	Asymmetric devices based on carbon nanotubes as detectors of sub-THz radiation			Type	Conference Article
	Year	2016	Publication	J. Phys.: Conf. Ser.	Abbreviated Journal	J. Phys.: Conf. Ser.
	Volume	741	Issue		Pages	012143 (1 to 6)
	Keywords	carbon nanotubes, CNT
	Abstract	Demand for efficient terahertz (THz) radiation detectors resulted in intensive study of the asymmetric carbon nanostructures as a possible solution for that problem. In this work, we systematically investigate the response of asymmetric carbon nanodevices to sub-terahertz radiation using different sensing elements: from dense carbon nanotube (CNT) network to individual CNT. We conclude that the detectors based on individual CNTs both semiconducting and quasi-metallic demonstrate much stronger response in sub-THz region than detectors based on disordered CNT networks at room temperature. We also demonstrate the possibility of using asymmetric detectors based on CNT for imaging in the THz range at room temperature. Further optimization of the device configuration may result in appearance of novel terahertz radiation detectors.
	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	1336
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	Author	Goltsman, G. N.; Shcherbatenko, M. L.; Lobanov, Y. V.; Kovalyuk, V. V.; Kahl, O.; Ferrari, S.; Korneev, A.; Pernice, W. H. P.
	Title	Superconducting nanowire single photon detector for coherent detection of weak optical signals			Type	Abstract
	Year	2016	Publication	LPHYS'16	Abbreviated Journal	LPHYS'16
	Volume		Issue		Pages	1-2
	Keywords	SSPD, SNSPD
	Abstract	Traditionally, photon detectors are operated in a direct detection mode counting incident photonswith a known quantum efficiency. This procedure allows one to detect weak sources of radiation but allthe information about its frequency is limited by the optical filtering/resonating structures used which arenot as precise as would be required for some practical applications. In this work we propose heterodynereceiver based on a photon counting mixer which would combine excellent sensitivity of a photon countingdetector and excellent spectral resolution given by the heterodyne technique. At present, Superconducting-Nanowire-Single-Photon-Detectors (SNSPDs) [1] are widely used in a variety of applications providing thebest possible combination of the sensitivity and speed. SNSPDs demonstrate lack of drawbacks like highdark count rate or autopulsing, which are common for traditional semiconductor-based photon detectors,such as avalanche photon diodes.In our study we have investigated SNSPD operated as a photon counting mixer. To fully understandits behavior in such a regime, we have utilized experimental setup based on a couple of distributedfeedback lasers irradiating at 1.5 micrometers, one of which is being the Local Oscillator (LO) and theother mimics the test signal [2]. The SNSPD was operated in the current mode and the bias currentwas slightly below of the critical current. Advantageously, we have found that LO power needed for anoptimal mixing is of the order of hundreds of femtowatts to a few picowatts, which is promising for manypractical applications, such as receiver matrices [3]. With use of the two lasers, one can observe thevoltage pulses produced by the detected photons, and the time distribution of the pulses reproduces thefrequency difference between the lasers, forming power response at the intermediate frequency which canbe captured by either an oscilloscope (an analysis of the pulse statistics is needed) or by an RF spectrumanalyzer. Photon-counting nature of the detector ensures quantum-limited sensitivity with respect to theoptical coupling achieved. In addition to the chip SNSPD with normal incidence coupling, we use thedetectors with a travelling wave geometry design [4]. In this case a NbN nanowire is placed on the topof a Si3N4 nanophotonic waveguide, thus increasing the efficient interaction length. For this reason it ispossible to achieve almost complete absorption of photons and reduce the detector footprint. This reducesthe noise of the device together with the expansion of the bandwidth. Integrated device scheme allowsus to measure the optical losses with high accuracy. Our approach is fully scalable and, along with alarge number of devices integrated on a single chip can be adapted to the mid and far IR ranges wherephoton-counting measurement may be beneficial as well [5].Acknowledgements: This work was supported in part by the Ministry of Education and Science of theRussian Federation, contract No. 14.B25.31.0007 and by RFBR grant No. 16-32-00465.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1220
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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
	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	1083-3668	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:27626901			Approved	no
	Call Number				Serial	1335
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	Author	Iomdina, E. N.; Seliverstov, S.; Sianosyan, A.; Teplyakova, K.; Rusova, A.; Goltsman, G.
	Title	The prospects of using the radiation for the assessment of corneal and scleral hydration			Type	Abstract
	Year	2016	Publication	Acta Ophthalmol.	Abbreviated Journal	Acta Ophthalmol.
	Volume	94	Issue		Pages
	Keywords	BWO, avalanche transit‐time diode, medicine, biology
	Abstract	Purpose 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. THz systems creating images in reflected beams are likely to become ideal instruments of noninvasive testing of corneal and scleral hydration degree as THz radiation is highly sensitive to water content. The paper aims at studying the transmittance and reflectance spectra of the cornea and the sclera of rabbit and human eyes, as well as those of the whole rabbit eye, in the frequency range of 0.13–0.32 THz. Methods The experiments were carried out on 3 corneas and 3 rabbit scleras, 2 whole rabbit eyes, and 3 human healthy adult scleras using a specially developed THz system based on reliable and easy‐to‐use continuous wave sources: a backward‐wave oscillator and an avalanche transit‐time diode. Results The transmittance spectra of the cornea and the sclera and the dependence of the reflection coefficient of these tissues in THz range on water percentage content were determined. Comparison of the rabbit cornea hydrated from 73.2% to 76.3% concentration by mass demonstrated an approximately linear relationship between THz reflectivity and water concentration. The decrease of free water concentration by 1% leads to a drop of the reflectance coefficient by 13%. The parameters studied displayed noticeable differences between the sclera and the cornea of rabbits and between rabbit sclera and human sclera. Conclusions Preliminary results demonstrate that the proposed technique, based on continuous THz radiation, may be used to create a device for noninvasive testing of corneal and scleral hydration, which has good potential of wide‐scale practical application. The work was supported by the Russian Foundation of Basic Research (grant No.15‐29‐03843)
	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	1755375X	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number				Serial	1333
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