Interaction and Quantum Decoherence in Disordered Conductors

TL;DR

This paper introduces a nonperturbative method to evaluate how electron-electron interactions affect weak localization and dephasing in disordered conductors, revealing finite dephasing times at zero temperature.

Contribution

It develops a nonperturbative approach to analyze the impact of interactions on quantum decoherence in disordered conductors, linking dephasing time to a specific function and clarifying limitations of perturbative methods.

Findings

Dephasing time remains finite at zero temperature due to interactions.

The effect of interactions on magnetoconductance is described by a specific function.

Perturbative calculations cannot unambiguously determine dephasing time.

Abstract

We present a nonperturbative approach which allows to evaluate the weak localization correction to the conductivity of disordered conductors in the presence of interactions. The effect of the electron-electron interaction on the magnetoconductance is described by the function A(t)\exp (-f(t)). The dephasing time is determined only by f(t), and this time remains finite down to T=0 due to the electron-electron interactions. In order to establish the relation between our nonperturbative analysis and the perturbative results the effect of interaction on the pre-exponent A(t) should be taken into account. The dephasing time cannot be unambiguously determined from a perturbative calculation.