Low-Temperature Dephasing in Disordered Conductors: the Effect of ``1/f'' Fluctuations

TL;DR

This paper investigates the low-temperature dephasing rate in disordered conductors, showing that defect dynamics, rather than static defects, can explain the observed saturation of dephasing rates at very low temperatures.

Contribution

It demonstrates that incorporating defect dynamics into models explains the apparent saturation of dephasing rates in disordered conductors at low temperatures.

Findings

Static defect models cannot account for dephasing rate saturation.

Defect dynamics can produce the observed saturation effect.

The study links 1/f fluctuations to dephasing behavior.

Abstract

Electronic quantum effects in disordered conductors are controlled by the dephasing rate of conduction electrons. This rate is expected to vanish with the temperature. We consider the very intriguing recently reported apparent saturation of this dephasing rate in several systems at very low temperatures. We show that the ``standard model'' of a conductor with static defects can {\em not} have such an effect. However, allowing some dynamics of the defects may produce it.