Universal long-time relaxation of nuclear spins in a disordered conductor

Abstract

The influence of fluctuations of the local density of states in dirty metal on the kinetics of nuclear magnetization is investigated. The large-scale fluctuations of the Korringa relaxation rate lead to a deviation from the typical exponential law. The nuclear spin diffusion promotes a new universal exponential regime at long times, when the exponent is independent of the constant of electron-nuclear interaction and is determined by the nuclear spin diffusion coefficient D s and by the electron diffusion coefficient D.