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Electron-phonon relaxation time in ultrathin tungsten silicon film
Cornell University
,
2016.
No. 1607.07321.
Sidorova M. V., Semenov A., Korneev A., Chulkova G., Korneeva Y., Mikhailov M., Devizenko A., Kozorezov A., Goltsman G.
Using amplitude-modulated absorption of sub-THz radiation (AMAR) method, we studied electron-phonon relaxation in thin disordered films of tungsten silicide. We found a response time ~ 800 ps at critical temperature Tc = 3.4 K, which scales as minus 3 in the temperature range from 1.8 to 3.4 K. We discuss mechanisms, which can result in a strong phonon bottle-neck effect in a few nanometers thick film and yield a substantial difference between the measured time, characterizing response at modulation frequency, and the inelastic electron-phonon relaxation time. We estimate the electron-phonon relaxation time to be in the range ~ 100-200 ps at 3.4 K.
Korneeva Y., Mikhailov M., Pershin Y. et al., Superconductor Science and Technology 2014 Vol. 27 No. 9 P. 095012
We fabricated and characterized nanowire superconducting single-photon detectors made of 4 nm thick amorphous Mo x Si1−x films. At 1.7 K the best devices exhibit a detection efficiency (DE) up to 18% at 1.2 <img /> wavelength of unpolarized light, a characteristic response time of about 6 ns and timing jitter of 120 ps. The ...
Added: March 31, 2015
Korneev A., Korneeva Y., Mikhailov M. et al., IEEE Transactions on Applied Superconductivity 2015 Vol. 25 No. 3 P. 1-4
We investigate the response mechanism of nanowire superconducting single-photon detectors (SSPDs) made of amorphous MoxSi1-x. We study the dependence of photon count and dark count rates on bias current in magnetic fields up to 113 mT at 1.7 K temperature. The observed behavior of photon counts is similar to the one recently observed in NbN ...
Added: March 31, 2015
Croitoru M. D., Shanenko A. A., Vagov A. et al., Journal of Superconductivity and Novel Magnetism 2016 Vol. 29 P. 605-609
We investigate how the interplay of quantum confinement and level broadening caused by disorder affects superconducting correlations in ultra-small metallic grains. We use the electron-phonon interaction-induced electron mass renormalization and the reduced static-path approximation of the BCS formalism to calculate the critical temperature as a function of the grain size. We show how the strong ...
Added: February 22, 2016
Schuck C., Pernice W., Minaeva O. et al., IEEE Transactions on Applied Superconductivity 2013 Vol. 23 No. 3
Added: March 2, 2015
Smirnov K., Vachtomin Y., Divochiy A. et al., Applied Physics Express 2015 Vol. 8 No. 2
Added: March 27, 2015
Elezov M. S., Ozhegov R., Goltsman G. et al., EPJ Web of Conferences 2017 Vol. 132 P. 1-2
Recently bright-light control of the SSPD has been demonstrated. This attack employed a "backdoor" in the detector biasing scheme. Under bright-light illumination, SSPD becomes resistive and remains "latched" in the resistive state even when the light is switched off. While the SSPD is latched, Eve can simulate SSPD single-photon response by sending strong light pulses, ...
Added: October 13, 2017
Sezonov Y. I., Ul’din A., Химическая физика 2009 Т. 28 № 12 С. 81-83
Изучен вклад электрон-фононного взаимодействия в проводимость углеродной нанотрубки. Получены аналитические формулы, описывающие зависимость проводимости нанотрубки от температуры, скорости звука, радиуса нанотрубки и линейной концентрации электронов. ...
Added: February 28, 2013
Pernice W., Schuck C., Minaeva O. et al., Nature Communications 2012 No. 3
Added: March 2, 2015
Smirnov K., Zolotov P., Divochiy A. et al., KnE Energy & Physics 2018 Vol. 2018 P. 83-89
We optimized technology of thin VN films deposition in order to study VN-based superconducting single-photon detectors. Investigation of the main VN film parameters showed that this material has lower resistivity compared to commonly used NbN. Fabricated from obtained films devices showed 100% intrinsic detection efficiency at 900 nm, at the temperature of 1.7 K starting ...
Added: October 25, 2019
Ryabchun S., Goltsman G., Kardakova A. et al., Physical Review B: Condensed Matter and Materials Physics 2016 Vol. 93 No. 6 P. 064506-064517
We report a study of the relaxation time of the restoration of the resistive superconducting state in single crystalline boron-doped diamond using amplitude-modulated absorption of (sub-)THz radiation (AMAR). The films grown on an insulating diamond substrate have a low carrier density of about 2.5×1021cm−3 and a critical temperature of about 2K. By changing the modulation ...
Added: August 15, 2016
Photon counting statistics of superconducting single-photon detectors made of a three-layer WSi film
Goltsman G., Florya I., Korneeva Y. et al., Low Temperature Physics 2018 Vol. 44 No. 3 P. 221-225
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 ...
Added: July 31, 2018
Korneeva Y., Smirnov K. V., Mikhailov M. et al., Superconductor Science and Technology 2014 No. 27
Added: March 2, 2015
Arutyunov K., Sedov E., Golokolenov I. et al., Физика твердого тела 2019 Т. 61 № 9 С. 1609-1613
Экспериментально исследовались высококачественные пленки алюминия на подложках из GaAs. Был обнаружен заметный рост критической температуры сверхпроводящего перехода с уменьшением толщины пленки. Эффект интерпретируется как проявление квантового размерного эффекта, влияющего как на плотность состояний электронов, так и на электрон-фононное взаимодействие. ...
Added: September 14, 2019
Ksenz A. S., Stolyarov V. S., Chekmazov S. V. et al., Physical Review B: Condensed Matter and Materials Physics 2018 Vol. 98 P. 155440
Proximity phenomena between superconductors and topological semimetals are at the heart of the search for novel quantum states of matter. Here we show that the epitaxial interface between one- to three-atomic-layer Pb and the Sb(111) substrate has extremely high electronic transparency. As a result, Pb loses its superconducting and even its metallic properties; its electronic ...
Added: January 27, 2020
Korneev A., Hubers H., Semenov A. et al., Physical Review B: Condensed Matter and Materials Physics 2014 Vol. 89
We have studied the influence of an externally applied magnetic field on the photon and dark count rates of meander-type niobium nitride superconducting nanowire single-photon detectors. Measurements have been performed at a temperature of 4.2 K, and magnetic fields up to 250 mT have been applied perpendicularly to the meander plane. While photon count rates ...
Added: March 2, 2015
Korneev Alexander, Korneeva Y., Manova N. et al., IEEE Transactions on Applied Superconductivity 2013 Vol. 23 No. 3 P. 2201204
In this paper, we present our approaches to the development of fiber-coupled superconducting single photon detectors with enhanced photon absorption. For such devices we have measured detection efficiency in wavelength range from 500 to 2000 nm. The best fiber coupled devices exhibit detection efficiency of 44.5% at 1310 nm wavelength and 35.5% at 1550 nm ...
Added: March 7, 2014
Kovalyuk V., Ferrari S., Kahl O. et al., Scientific Reports 2017 Vol. 7 No. 1 P. 1-9
While single photon detectors provide superior intensity sensitivity, spectral resolution is usually lost after the detection event. Yet for applications in low signal infrared spectroscopy recovering information about the photon's frequency contributions is essential. Here we use highly efficient waveguide integrated superconducting single-photon detectors for on-chip coherent detection. In a single nanophotonic device, we demonstrate ...
Added: October 13, 2017
Beck M., Rousseau I., Klammer M. et al., Physical Review Letters 2013 Vol. 110 No. 26
Added: March 2, 2015
Klimin S. A., Popova E., Popova M. N., Journal of Physics: Conference Series 2019 Vol. 1389 No. 1 P. 012039
We present low-temperature far-infrared study of Sm2BaNiO5. The lowest-frequency phonon of Sm2BaNiO5 generated by the motion of the Sm3+ ion demonstrates anomalous behaviour at temperatures lower than the Néel temperature, T<TN=55 K. This phonon hardens at the magnetic ordering although its frequency shift does not follow the magnetic order parameter. The observed phenomenon is responsible for ...
Added: December 19, 2019
Kardakova A. I., Coumou P. C., Finkel M. I. et al., IEEE Transactions on Applied Superconductivity 2015 Vol. 25 No. 3 P. 1-4
We have measured the energy relaxation times from the electron bath to the phonon bath in strongly disordered TiN films grown by atomic layer deposition. The measured values of τeph vary from 12 to 91 ns. Over a temperature range from 3.4 to 1.7 K, they follow T-3 temperature dependence, which are consistent with values ...
Added: October 15, 2015
Bristol : IOP Publishing, 2019
We present low-temperature far-infrared study of Sm2BaNiO5. The lowest-frequency phonon of Sm2BaNiO5 generated by the motion of the Sm3+ ion demonstrates anomalous behaviour at temperatures lower than the Néel temperature, T<TN=55 K. This phonon hardens at the magnetic ordering although its frequency shift does not follow the magnetic order parameter. The observed phenomenon is responsible for ...
Added: October 30, 2019
Krause S., Mityashkin V., Antipov S. et al., IEEE Transactions on Terahertz Science and Technology 2017 Vol. 7 No. 1 P. 53-59
In this paper, we investigated the influence of the GaN buffer layer on the phonon escape time of phonon-cooled hot electron bolometers (HEBs) based on NbN material and compared our findings to conventionally employed Si substrate. The presented experimental setup and operation of the HEB close to the critical temperature of the NbN film allowed ...
Added: February 22, 2017
Elezov M. S., Ozhegov R., Kurochkin Y. V. et al., EPJ Web of Conferences 2015 Vol. 103 P. 10002-p.1-10002-p.2
Nowadays, the superconducting single-photon detectors (SSPDs) are used in Quantum Key Distribution (QKD) instead of single-photon avalanche photodiodes. Recently bright-light control of the SSPD has been demonstrated. This attack employed a "backdoor" in the detector biasing technique. We developed the autoreset system which returns the SSPD to superconducting state when it is latched. We investigate ...
Added: October 13, 2017
Shurakov A., Tong C. -., Grimes P. et al., IEEE Transactions on Terahertz Science and Technology 2015 Vol. 5 No. 1 P. 81-84
In this paper, we propose and present data from a fast THz detector based on the repurpose of hot electron bolometer mixers (HEB) fabricated from superconducting NbN thin film. This detector is essentially a traditional NbN bolometer element that operates under the influence of a microwave pump. The injected microwave power serves the dual purpose ...
Added: February 19, 2016