Weak localization in two and three dimensions: Dephasing by zero-point motion

Abstract

A mechanism leading to a temperature-independent dephasing time, ${\ensuremath{\tau}}_{\ensuremath{\varphi}}$, in the weakly localized regime is discussed. It is shown that the time-reversed complementary scattering paths which lead to weak localization experience a relative phase shift due to the zero-point motion of the ions in the material. By use of a simple model it is shown that this mechanism can explain the saturation of ${\ensuremath{\tau}}_{\ensuremath{\varphi}}$ which is seen at low temperatures in a wide variety of systems.