|   | 
Details
   web
Records
Author (up) Usadel, Klaus D.
Title Generalized diffusion equation for superconducting alloys Type Journal Article
Year 1970 Publication Phys. Rev. Lett. Abbreviated Journal Phys. Rev. Lett.
Volume 25 Issue 8 Pages 507
Keywords
Abstract Eilenberger's transportlike equations for a superconductor of type II can be simplified very much in the dirty limit. In this limit a diffusionlike equation is derived which is the generalization of the de Gennes-Maki theory for dirty superconductors to arbitrary values of the order parameter.
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 920
Permanent link to this record
 

 
Author (up) Vercruyssen, N.; Verhagen, T. G. A.; Flokstra, M. G.; Pekola, J. P.; Klapwijk, T. M.
Title Evanescent states and nonequilibrium in driven superconducting nanowires Type Journal Article
Year 2012 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 85 Issue Pages 224503(1-10)
Keywords Al HEB, Al superconducting nanowire, global state, bimodal state, quasiclassical kinetic equations, Usadel equation
Abstract We study the nonlinear response of current transport in a superconducting diffusive nanowire between normal reservoirs. We demonstrate theoretically and experimentally the existence of two different superconducting states appearing when the wire is driven out of equilibrium by an applied bias, called the global and bimodal superconducting states. The different states are identified by using two-probe measurements of the wire, and measurements of the local density of states with tunneling probes. The analysis is performed within the framework of the quasiclassical kinetic equations for diffusive superconductors.
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 898
Permanent link to this record
 

 
Author (up) Verevkin, A. A.; Ptitsina, N. G.; Chulcova, G. M.; Gol'Tsman, G. N.; Gershenzon, E. M.; Yngvesson, K. S.
Title Determination of the limiting mobility of a two-dimensional electron gas in AlxGa1-xAs/GaAs heterostructures and direct measurement of the energy relaxation time Type Journal Article
Year 1996 Publication Phys. Rev. B Condens. Matter. Abbreviated Journal Phys. Rev. B Condens. Matter.
Volume 53 Issue 12 Pages R7592-R7595
Keywords 2DEG, AlGaAs/GaAs heterostructures
Abstract We present results for a method to measure directly the energy relaxation time (τe) for electrons in a single AlxGa1−xAs/GaAs heterojunction; measurements were performed from 1.6 to 15 K under quasiequilibrium conditions. We find τeαT−1 below 4 K, and τe independent of T above 4 K. We have also measured the energy-loss rate, ⟨Q⟩, by the Shubnikov-de Haas technique, and find ⟨Q⟩α(T3e−T3) for T<~4.2 K; Te is the electron temperature. The values and temperature dependence of τe and ⟨Q⟩ for T<4 K agree with calculations based on piezoelectric and deformation potential acoustic phonon scattering. At 4.2 K, we can also estimate the momentum relaxation time, τm, from our measured τe. This leads to a preliminary estimate of the phonon-limited mobility at 4.2 K of μ=3×107 cm2/Vs (ns=4.2×1011 cm−2), which agrees well with published numerical calculations, as well as with an earlier indirect estimate based on measurements on a sample with much higher mobility.
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 0163-1829 ISBN Medium
Area Expedition Conference
Notes PMID:9982274 Approved no
Call Number Serial 1612
Permanent link to this record
 

 
Author (up) Vodolazov, D. Y.; Korneeva, Y. P.; Semenov, A. V.; Korneev, A. A.; Goltsman, G. N.
Title Vortex-assisted mechanism of photon counting in a superconducting nanowire single-photon detector revealed by external magnetic field Type Journal Article
Year 2015 Publication Phys. Rev. B Abbreviated Journal Phys. Rev. B
Volume 92 Issue 10 Pages 104503 (1 to 9)
Keywords SSPD, SNSPD
Abstract We use an external magnetic field to probe the detection mechanism of a superconducting nanowire single-photon detector. We argue that the hot belt model (which assumes partial suppression of the superconducting order parameter Δ across the whole width of the superconducting nanowire after absorption of the photon) does not explain observed weak-field dependence of the photon count rate (PCR) for photons with λ=450nm and noticeable decrease of PCR (with increasing the magnetic field) in a range of the currents for photons with wavelengths λ=450–1200nm. Found experimental results for all studied wavelengths can be explained by the vortex hot spot model (which assumes partial suppression of Δ in the area with size smaller than the width of the nanowire) if one takes into account nucleation and entrance of the vortices to the photon induced hot spot and their pinning by the hot spot with relatively large size and strongly suppressed Δ.
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 1098-0121 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1343
Permanent link to this record
 

 
Author (up) Vodolazov, D. Y.; Manova, N. N.; Korneeva, Y. P.; Korneev, A. A.
Title Timing jitter in NbN superconducting microstrip single-photon detector Type Journal Article
Year 2020 Publication Phys. Rev. Applied Abbreviated Journal Phys. Rev. Applied
Volume 14 Issue 4 Pages 044041 (1 to 8)
Keywords NbN SSPD, SNSPD
Abstract We experimentally study timing jitter of single-photon detection by NbN superconducting strips with width w ranging from 190 nm to 3μm. We find that timing jitter of both narrow (190 nm) and micron-wide strips is about 40 ps at currents where internal detection efficiency η saturates and it is close to our instrumental jitter. We also calculate intrinsic timing jitter in wide strips using the modified time-dependent Ginzburg-Landau equation coupled with a two-temperature model. We find that with increasing width the intrinsic timing jitter increases and the effect is most considerable at currents where a rapid growth of η changes to saturation. We relate it with complicated vortex and antivortex dynamics, which depends on a photon’s absorption site across the strip and its width. The model also predicts that at current close to depairing current the intrinsic timing jitter of a wide strip could be about ℏ/kBTc (Tc is a critical temperature of superconductor), i.e., the same as for a narrow strip.
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 2331-7019 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1788
Permanent link to this record