Dephasing in disordered metals with superconductive grains.
The temperature dependence of electron dephasing time tau(phi)(T) is calculated for a disordered metal with a small concentration of superconductive grains. Above the macroscopic superconducting transition line, when electrons in the metal are normal, Andreev reflection from the grains leads to a nearly temperature-independent contribution to the dephasing rate. In a broad temperature range tau(-1)(phi)(T) strongly exceeds the prediction of the classical theory of dephasing in normal disordered conductors, whereas magnetoresistance is dominated (in two dimensions) by the Maki-Tompson correction and is positive.
Skvortsov
M A
MA
L. D. Landau Institute for Theoretical Physics, Moscow 119334, Russia. skvor@itp.ac.ru
Larkin
A I
AI
Feigel'man
M V
MV