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Title: Low-voltage current noise in long quantum superconductor/insulator/normal-metal/insulator/superconductor junctions.

Abstract

The current noise in long superconductor/insulator/normal-metal/insulator/superconductor junctions at low temperatures is sensitive to the population of the subgap states, which is far from equilibrium even at low bias voltages. A nonequilibrium distribution is established due to an interplay between voltage-driven interlevel Landau-Zener transitions and intralevel inelastic relaxation. The Fano factor (the ratio of the zero-frequency noise to the dc current) is enhanced drastically, being proportional to the number of times which a particle flies along the Andreev trajectory before it escapes from the level due to inelastic scattering. For weak Landau-Zener transitions, the enhancement is even larger due to a smaller dc current.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); Academy of Finland; ULTI Program; Russian Foundation for Basic Research Grant
OSTI Identifier:
919349
Report Number(s):
ANL/MSD/JA-60405
Journal ID: ISSN 0163-1829; PRBMDO; TRN: US200822%%33
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Rev. B; Journal Volume: 76; Journal Issue: 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
42 ENGINEERING; SUPERCONDUCTING JUNCTIONS; ELECTRICAL INSULATORS; METALS; ELECTRIC POTENTIAL; NOISE; LANDAU-ZENER FORMULA; FANO FACTOR; INELASTIC SCATTERING

Citation Formats

Kopnin, N. B., Galperin, Y. M., Vinokur, V., Materials Science Division, Helsinki Univ. Tech., L.D. Landau Inst. for Theoretical Physics, Univ. Oslo, and A.F. Ioffe Physico-Tech. Inst. of Russian Academy of Sciences. Low-voltage current noise in long quantum superconductor/insulator/normal-metal/insulator/superconductor junctions.. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.76.100504.
Kopnin, N. B., Galperin, Y. M., Vinokur, V., Materials Science Division, Helsinki Univ. Tech., L.D. Landau Inst. for Theoretical Physics, Univ. Oslo, & A.F. Ioffe Physico-Tech. Inst. of Russian Academy of Sciences. Low-voltage current noise in long quantum superconductor/insulator/normal-metal/insulator/superconductor junctions.. United States. doi:10.1103/PhysRevB.76.100504.
Kopnin, N. B., Galperin, Y. M., Vinokur, V., Materials Science Division, Helsinki Univ. Tech., L.D. Landau Inst. for Theoretical Physics, Univ. Oslo, and A.F. Ioffe Physico-Tech. Inst. of Russian Academy of Sciences. Mon . "Low-voltage current noise in long quantum superconductor/insulator/normal-metal/insulator/superconductor junctions.". United States. doi:10.1103/PhysRevB.76.100504.
@article{osti_919349,
title = {Low-voltage current noise in long quantum superconductor/insulator/normal-metal/insulator/superconductor junctions.},
author = {Kopnin, N. B. and Galperin, Y. M. and Vinokur, V. and Materials Science Division and Helsinki Univ. Tech. and L.D. Landau Inst. for Theoretical Physics and Univ. Oslo and A.F. Ioffe Physico-Tech. Inst. of Russian Academy of Sciences},
abstractNote = {The current noise in long superconductor/insulator/normal-metal/insulator/superconductor junctions at low temperatures is sensitive to the population of the subgap states, which is far from equilibrium even at low bias voltages. A nonequilibrium distribution is established due to an interplay between voltage-driven interlevel Landau-Zener transitions and intralevel inelastic relaxation. The Fano factor (the ratio of the zero-frequency noise to the dc current) is enhanced drastically, being proportional to the number of times which a particle flies along the Andreev trajectory before it escapes from the level due to inelastic scattering. For weak Landau-Zener transitions, the enhancement is even larger due to a smaller dc current.},
doi = {10.1103/PhysRevB.76.100504},
journal = {Phys. Rev. B},
number = 2007,
volume = 76,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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