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Precise measurement of the thermal conductivity of superconductor
AIP Conference Proceedings. 2018. Vol. 1936. No. 1. P. 020003-1-020003-4.
Measuring the thermal properties such as the heat capacity provide information about intrinsic mechanisms operated inside. In general, the ratio between electron and phonon specific heat Ce/Cp shows how the absorbed energy shared between electron and phonon subsystems. In this work we make estimations for amplitude-modulated absorption of THz radiation technique for investigation of the ratio Ce/Cp in superconducting Niobium Nitride (NbN) at T = Tc . Our results indicates that experimentally the frequency of modulation has to be extra large to extract the quantity. We perform a new technique allowed to work at low frequency with accurately measurement of absorbed power.
Publication based on the results of:
Pentina I. V., Smirnov K., Ryabchun S. et al., Technical Physics 2012 Vol. 57 No. 7 P. 971-974
We present the results of our studies of the semiconducting superlattice (SSL) frequency multiplier and its application as part of the solid state local oscillator (LO) in the terahertz heterodyne receiver based on a NbN hot-electron bolometer (HEB) mixer. We show that the SSL output power level increases as the ambient temperature is lowered to ...
Added: October 12, 2017
Smirnov K., Золотов Ф. И., Romanov N. et al., Journal of Physics: Conference Series 2018 No. 1124 P. 1-6
The research of ultrathin vanadium nitride (VN) films as a promising candidate for superconducting single-photon detectors (SSPD) is presented. The electron diffusivity measurements are performed for such devices. Devices that were fabricated out from 9.9 nm films had diffusivity coefficient of 0.41 cm2 /s and from 5.4 nm – 0.54 cm2 /s. Obtained values are ...
Added: December 27, 2018
Smirnov K., Вахтомин Ю. Б., Смирнов А. В. et al., Вестник Новосибирского государственного университета. Серия: Физика 2010 Т. 5 № 4 С. 63-67
This work presents the results of the development and fabrication of sensitive and ultrafast detectorsbased on thin film superconducting nanostructures: hot-electron bolometers (HEBs) and visible and infrared superconducting singe photon detectors (SSPDs). The main operational principles of the superconducting devices are presentedas well as the technology of fabrication of the detectors and their main types ...
Added: October 12, 2017
Золотов Ф. И., Goltsman G., smirnov e. et al., Journal of Physics: Conference Series 2018 No. 1124 P. 1-4
We demonstrate superconducting niobium nitride nanowires folded on top of lithium
niobate substrate. We report of 6% system detection efficiency at 20 s-1 dark count rate at
telecommunication wavelength (1550 nm). Our results shown great potential for the use of NbN
nanowires in the field of linear and nonlinear integrated quantum photonics. ...
Added: December 27, 2018
Золотов Ф. И., Divochiy A., Vakhtomin Y. et al., Journal of Physics: Conference Series 2018 No. 1124 P. 1-6
We researched the relation between deposition and ultra-thin VN films parameters.
To conduct the experimental study we varied substrate temperature, Ar and N2 partial pressures
and deposition rate. The study allowed us to obtain the films with close to the bulk values
transition temperatures and implement such samples in order to fabricate superconducting
single-photon detectors ...
Added: December 27, 2018
Lusche R., Semenov A., Il'in K. et al., IEEE Transactions on Applied Superconductivity 2013 Vol. 23 No. 3 P. 2200205-1-2200205-5
We present thorough measurements of the intrinsic detection efficiency in the wavelength range from 350 to 2500 nm for meander-type TaN and NbN superconducting nanowire single-photon detectors with different widths of the nanowire. The width varied from 70 nm to 130 nm. The open-beam configuration allowed us to accurately normalize measured spectra and to extract ...
Added: March 13, 2014
Korneeva Y., Vodolazov D. Y., Semenov A. V. et al., Physical Review Applied 2018 Vol. 9 No. 6 P. 1-13
We demonstrate experimentally that single photon detection can be achieved in micron-wide NbN bridges, with widths ranging from 0.53\,μm to 5.15\,μm and for photon-wavelengths from 408\,nm to 1550\,nm. The microbridges are biased with a dc current close to the experimental critical current, which is estimated to be about 50\the theoretically expected depairing current. These results ...
Added: May 26, 2018
Lobanov Y., Shcherbatenko M., Finkel M. I. et al., IEEE Transactions on Applied Superconductivity 2015 Vol. 25 No. 3 P. 1-4
Traditionally, hot-electron-bolometer (HEB) mixers are employed for THz and “super-THz” heterodyne detection. To explore the near-IR spectral range, we propose a fiber-coupled NbN film based HEB mixer. To enhance the incident-light absorption, a quasi-antenna consisting of a set of parallel stripes of gold is used. To study the antenna effect on the mixer performance, we ...
Added: October 15, 2015
Золотов Ф. И., Divochiy A., Vakhtomin Y. et al., AIP Conference Proceedings 2018 Vol. 1936 No. 1 P. 020019-1-020019-6
We used technology of making high-efficiency superconducting single-photon detectors as a basis for improvement of photon-number-resolving devices. By adding optical cavity and using an improved NbN superconducting film, we enhanced previously reported system detection efficiency at telecom range for such detectors. Our results show that implementation of optical cavity helps to develop four-section device with ...
Added: March 14, 2018
Zolotov Philipp, Divochiy A., Vakhtomin Y. et al., Journal of Physics: Conference Series 2017 Vol. 917 No. 062037 P. 1-6
We report on development of superconducting single-photon detectors (SSPD) with
high intrinsic quantum efficiency in the wavelength range 1.31 – 3.3 μm. By optimization of
the NbN film thickness and its compound, we managed to improve detection efficiency of the
detectors in the range up to 3.3 μm. Optimized devices showed intrinsic quantum efficiencies
as high as 10% at ...
Added: November 24, 2017
Lusche R., Semenov A., Ilin K. et al., Journal of Applied Physics 2014 Vol. 116 No. 4 P. 043906-1-043906-9
A thorough spectral study of the intrinsic single-photon detection efficiency in superconducting TaN and NbN nanowires with different widths has been performed. The experiment shows that the cut-off of the intrinsic detection efficiency at near-infrared wavelengths is most likely controlled by the local suppression of the barrier for vortex nucleation around the absorption site. Beyond ...
Added: February 24, 2016
Золотов Ф. И., Smirnov K., Divochiy A. et al., Optics Letters 2018 Vol. 43 No. 24 P. 6085-6088
We demonstrate niobium nitride based superconducting single-photon detectors sensitive in the spectral range 452–2300 nm. The system performance was tested in a real-life experiment with correlated photons generated by means of spontaneous parametric downconversion, where one photon was in the visible range and the other was in the infrared range. We measured a signal to noise ...
Added: December 27, 2018
Peltonen J. T., Astafiev O. V., Korneeva Y. P. et al., Physical Review B: Condensed Matter and Materials Physics 2013 Vol. 88 P. 220506-1-220506-5
We demonstrate evidence of coherent magnetic flux tunneling through superconducting nanowires patterned in a thin highly disordered NbN film. The phenomenon is revealed as a superposition of flux states in a fully metallic superconducting loop with the nanowire acting as an effective tunnel barrier for the magnetic flux, and reproducibly observed in different wires. The ...
Added: March 13, 2014
Dryazgov M., Semenov A., Manova N. et al., Journal of Physics: Conference Series 2020 Vol. 1695 Article 012195
The present paper describes a modelling of normal domain evolution in superconducting strip of micron width using solving differential equations describing the temperature and current changes. The solving results are compared with experimental data. This comparison demonstrates the high accuracy of the model. In future, it is possible to employ this model for improvement of ...
Added: February 24, 2021
Shcherbatenko M., Elezov M., Manova N. et al., Applied Physics Letters 2021 Vol. 118 Article 181103
High sensitivity imaging at the level of single photons is an invaluable tool in many areas, ranging from microscopy to astronomy. However, development of single-photon sensitive detectors with high spatial resolution is very non-trivial. Here we employ the singlepixel imaging approach and demonstrate a proof-of-principle single-pixel single-photon imaging setup. We overcome the problem of low ...
Added: May 6, 2021
Korneeva Y., Золотов Ф. И., Korneev A., Superconductor Science and Technology 2021 P. 1-10
We report our study of detection efficiency (DE) saturation in wavelength range 400 - 1550 nm for the NbN Superconducting Microstrip Single-Photon Detectors (SMSPD) featuring the strip width up to 3 μm. We observe an expected decrease of the $DE$ saturation plateau with the increase of photon wavelength and decrease of film sheet resistance. At ...
Added: June 9, 2021
Baeva E., Sidorova M. V., Korneev A. et al., Physical Review Applied 2018 Vol. 10 P. 1-8
We investigate thermal properties of a NbN single-photon detector capable of unit internal detection efficiency. Using an independent calibration of the coupling losses we determine the absolute
optical power absorbed by the NbN film and, via a resistive superconductor thermometry, the thermal resistance Z(T) of the NbN film in dependence of temperature. In principle, this approach
permits ...
Added: January 3, 2019
Antipov A., Seleznev V., Vakhtomin Y. et al., IOP Conference Series: Materials Science and Engineering (MSE) 2020 Vol. 781 No. 1 P. 012011-1-012011-5
Spectral characteristics of WSi and NbN superconducting single-photon detectors with different surface resistance and width of nanowire strips have been investigated in the wavelength range of 1.3-2.5 µm. WSi structures with narrower strips demonstrated better performance for detection of single photons in longer wavelength range. The difference in normalized photon count rate for such structures ...
Added: December 10, 2020
Budkov Y., Kolesnikov A. L., Polymer Science - Series C 2018 Vol. 60 No. Supplement 1 P. 148-159
Theoretical models of the conformational behavior of flexible polymer chains in mixed solvents enunciated in the world literature during the last decade are critically reviewed. Models describing different mechanisms of coil-to-globule transitions in a good solvent induced by cosolvent addition are highlighted. Special attention is given to the analysis of theoretical approaches to describing the ...
Added: November 30, 2018
Kalmykov A., Melentiev P., Balykin V., Laser Physics Letters 2020 Vol. 17 No. 4 P. 045901
In this paper we present measurements and comparison of SPP propagation length at the practically important telecom wavelength (1560 nm) as well as in the near-infrared and visible spectral ranges. The measurements were carried out for plane SPP waves excited on Ag film surface using optical microscopy of SPP waves in the far field. We ...
Added: January 15, 2021
M. : Faculty of Physics, MSU, 2017
The Low Temperature Physics Conference is an international event held every three years, under the auspices of the IUPAP through its Commission C5 on Low Temperature Physics. The aim of these conferences is to exchange information and views among the members of the international scientific community in the general field of Low Temperature Physics. It ...
Added: October 1, 2017
Kuzmichev S. A., Kuzmicheva T. E., Tchesnokov S. N. et al., Journal of Superconductivity and Novel Magnetism 2016 Vol. 29 No. 4 P. 1111-1116
We present temperature dependences of the large and the small superconducting gaps measured directly by SnS-Andreev spectroscopy in various Fe-based superconductors and MgB2. The experimental L,S(T ) are wellfitted with a two-gap model based on Moskalenko and Suhl system of equations (supplemented with a BCS integral renormalization). From the fitting procedure, we estimate the key ...
Added: March 19, 2016
Boldyrev K., Романов А., Хаула Е. et al., Journal of the American Ceramic Society 2019 Vol. 102 No. 5 P. 2745-2751
Single crystal of TlCl was doped with NIR photoluminescent univalent bismuth cations by prolonged immersion in liquid bismuth metal. The ion exchange Tl+ + Bi0 ↔ Tl0 + Bi+ at the crystal surface with subsequent Bi+ migration to the bulk are expected to drive the doping process. Contrary with Bi‐doped TlCl crystals, grown by Bridgman method, the ion exchange does ...
Added: February 8, 2019
Казанцев Д. В., Казанцева Е. А., Кузнецов Е. В. et al., Известия РАН. Серия физическая 2017 Т. 81 № 12 С. 1709-1714
Описаны принципы работы безапертурного сканирующего микроскопа ближнего оптического поля (ASNOM). Зондом в приборе служит металлизированная игла атомно-силового микроскопа, и оптическое взаимодействие с объектами на поверхности локализовано вблизи ее острия размером в несколько нанометров. Тело иглы имеет длину в несколько микрон, и это обеспечивает высокую эффективность ее электромагнитного взаимодействия с падающими на нее извне и излучаемыми ...
Added: December 6, 2020