Magnetic field dependence of relaxation times in nonequilibrium superconductors
Magnetic field dependence of relaxation times in nonequilibrium superconductors
复制标题
非平衡超导体中弛豫时间的磁场依赖性
DOI：
10.1007/bf00115571
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发表时间：
1978
影响因子：
2
通讯作者：
M. Tinkham
中科院分区：
文献类型：
--
作者：
A. Kadin;W. Skocpol;M. Tinkham
本文通过分析长锡微桥在Tc（H）附近平行场中的I-V特性，研究了磁场对超导体非平衡准粒子弛豫过程的影响。根据Skocpol、比斯利和Tinkham的理论，我们取给定相位滑移中心的微分电阻（PSC）近似等于桥长为2（D TR）1/2的非平衡区的法向电阻Rn，其中D是准粒子扩散常数，TR是横模（分支不平衡）弛豫时间。从我们的数据中推断的TRas的大小和温度和场的依赖性与Schmid和Schön导出的存在对破缺时的横模弛豫时间的大小和温度和场的依赖性一致。纵向模式的不平衡解释的局部加热成比例的IV，并在I-V特性的结果失真进行了校正。我们的大多数样品都包含一个故意的弱点，具有降低的临界电流Ic，这隔离了单个PSC并降低了散热（~ Ic 2 Rn）。
We have investigated the effects of a magnetic fieldHon nonequilibrium quasiparticle relaxation processes in superconductors by analyzing the I–V characteristics of long tin microbridges in a parallel field nearTc(H). Following Skocpol, Beasley, and Tinkham, we take the differential resistance of a given phase-slip center (PSC) to be approximately equal to the normal resistanceRnof a nonequilibrium region of the bridge with length 2(DΤR)1/2, whereDis the quasiparticle diffusion constant andΤRis the transverse mode (branch imbalance) relaxation time. The magnitude and the temperature and field dependence ofΤRas inferred from our data agree well with those of the transverse mode relaxation time in the presence of pair-breaking, derived by Schmid and Schön. The longitudinal mode disequilibrium is interpreted in terms of local heating proportional toIV, and the resulting distortions in the I–V characteristics are corrected. Most of our samples contain a deliberate weak spot with a depressed critical currentIc, which isolates a single PSC and lowers the heat dissipation(~Ic2Rn).