Anomalous temperature and disorder dependence of the electron-phonon scattering time in impure metals

Abstract

We have measured the electron-phonon scattering time, tau(ep), in disordered metals at liquid-helium temperatures, using weak-localization method. The temperature and disorder dependence of tau(ep), is determined for AgPd and AuPd thick films, and V100-xAlx alloys. In all three cases, we find an anomalous temperature and disorder dependence of tau(ep)(-1) proportional to T(2)l where l is the electron elastic mean free path. This temperature and disorder behavior cannot be explained in terms of current theoretical concepts for the electron-phonon interaction in impure conductors. Current theory predicts a form of either tau(ep)(-1) proportional to T(4)l or tau(ep)(-1) proportional to T(2)l(-1) in the dirty limit, depending on the nature of the defects. (C) 2003 Elsevier Science B.V. All rights reserved.