Thermal noise in superconducting quantum point contacts

被引:72
作者
MartinRodero, A [1 ]
Yeyati, AL [1 ]
GarciaVidal, FJ [1 ]
机构
[1] UNIV LONDON IMPERIAL COLL SCI & TECHNOL, BLACKETT LAB, CONDENSED MATTER THEORY GRP, LONDON SW7 2BZ, ENGLAND
关键词
D O I
10.1103/PhysRevB.53.R8891
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We present a theory for the frequency-dependent current fluctuations in superconducting quantum point contacts (SQPC) within the dc transport regime. This theory is valid for any barrier transparency between the tunnel and ballistic limits, yielding an analytical expression for the fluctuations spectrum in the subgap region. It is shown that the level of noise in a quasiballistic SQPC may have a huge increase in comparison with the case of a normal contact carrying the same average current. The effect of this high level of noise on the actual observability of the current-phase relation for a ballistic point contact is discussed in connection with recent experimental measurements.
引用
收藏
页码:R8891 / R8894
页数:4
相关论文
共 25 条
[1]  
[Anonymous], 1978, SOV J LOW TEMP PHYS
[2]   AC JOSEPHSON EFFECT IN A SINGLE QUANTUM CHANNEL [J].
AVERIN, D ;
BARDAS, A .
PHYSICAL REVIEW LETTERS, 1995, 75 (09) :1831-1834
[3]  
AVERIN D, UNPUB
[4]   JOSEPHSON CURRENT THROUGH A SUPERCONDUCTING QUANTUM POINT CONTACT SHORTER THAN THE COHERENCE LENGTH [J].
BEENAKKER, CWJ ;
VANHOUTEN, H .
PHYSICAL REVIEW LETTERS, 1991, 66 (23) :3056-3059
[5]   THEORY OF SUBHARMONIC GAP STRUCTURE IN SUPERCONDUCTING MESOSCOPIC TUNNEL CONTACTS [J].
BRATUS, EN ;
SHUMEIKO, VS ;
WENDIN, G .
PHYSICAL REVIEW LETTERS, 1995, 74 (11) :2110-2113
[6]   SCATTERING-THEORY OF THERMAL AND EXCESS NOISE IN OPEN CONDUCTORS [J].
BUTTIKER, M .
PHYSICAL REVIEW LETTERS, 1990, 65 (23) :2901-2904
[7]  
CUEVAS JC, UNPUB
[8]   CONTACT RESISTANCE IN THE SCANNING TUNNELING MICROSCOPE AT VERY SMALL DISTANCES [J].
FERRER, J ;
MARTINRODERO, A ;
FLORES, F .
PHYSICAL REVIEW B, 1988, 38 (14) :10113-10115
[9]   A UNIFIED THEORY OF CLEAN JOSEPHSON-JUNCTIONS [J].
FURUSAKI, A ;
TSUKADA, M .
PHYSICA B, 1990, 165 :967-968
[10]   QUASIPARTICLE AND PHONON LIFETIMES IN SUPERCONDUCTORS [J].
KAPLAN, SB ;
CHI, CC ;
LANGENBERG, DN ;
CHANG, JJ ;
JAFAREY, S ;
SCALAPINO, DJ .
PHYSICAL REVIEW B, 1976, 14 (11) :4854-4873