Dephasing in Disordered Conductors due to Fluctuating Electric Fields

TL;DR

This paper introduces a new theoretical approach to calculate how fluctuating electric fields cause dephasing in disordered conductors, aligning well with experimental observations.

Contribution

It develops a novel eikonal expansion for the Cooperon to analyze electric field-induced dephasing in disordered conductors with arbitrary fluctuations.

Findings

Dephasing rate is derived for random electric field fluctuations with arbitrary covariance.

In time-dependent fields, the dephasing rate scales with the square root of electromagnetic power.

Results agree with experimental data by Wang and Lindelof.

Abstract

We develop a novel eikonal expansion for the Cooperon to study the effect of space- and time-dependent electric fields on the dephasing rate of disordered conductors. For randomly fluctuating fields with arbitrary covariance we derive a general expression for the dephasing rate which is free of infrared divergencies in reduced dimensions. For time-dependent external fields with finite wavelength and sufficiently small amplitude we show that the dephasing rate is proportional to the square root of the electromagnetic power coupled into the system, in agreement with data by Wang and Lindelof [Phys. Rev. Lett. {\bf{59}}, 1156 (1987)].