The origin of Mooij correlations in disordered metals

Sergio Ciuchi,Domenico Di Sante,Vladimir Dobrosavljević,Simone Fratini

doi:10.1038/s41535-018-0119-y

Abstract

Sufficiently disordered metals display systematic deviations from the behavior predicted by semi-classical Boltzmann transport theory. Here the scattering events from impurities or thermal excitations can no longer be considered as additive-independent processes, as asserted by Matthiessen’s rule following from this picture. In the intermediate region between the regime of good conduction and that of insulation, one typically finds a change of sign of the temperature coefficient of resistivity, even at elevated temperature spanning ambient conditions, a phenomenology that was first identified by Mooij in 1973. Traditional weak coupling approaches to identify relevant corrections to the Boltzmann picture focused on long-distance interference effects such as “weak localization”, which are especially important in low dimensions (1D and 2D) and close to the zero-temperature limit. Here we formulate a strong-coupling approach to tackle the interplay of strong disorder and lattice deformations (phonons) in bulk three-dimensional metals at high temperatures. We identify a polaronic mechanism of strong disorder renormalization, which describes how a lattice locally responds to the relevant impurity potential. This mechanism, which quantitatively captures the Mooij regime, is physically distinct and unrelated to Anderson localization, but realizes early seminal ideas of Anderson himself, concerning the interplay of disorder and lattice deformations.

Highlights

Identifying physical mechanisms that control electronic transport in materials have long been recognized as a central task in condensed matter physics
We show that important local correlations between the impurity potential and the induced lattice deformations directly cause the breakdown of Matthiessen’s rule, and allow quantitative description of Mooij correlations found around the MIR limit
The temperature coefficient of the resistivity can be addressed by performing an expansion in the lattice fluctuations, as these are responsible for the leading ρ ∝ T term

Summary

Introduction

Identifying physical mechanisms that control electronic transport in materials have long been recognized as a central task in condensed matter physics. A surprisingly robust phenomenology describing how the TCR changes sign around the MIR limit has been established by Mooij in the early 1970s,5 noticing that the slope of the resistivity curves linearly (anti)correlates with the extrapolated zero-temperature value ρ0, which has subsequently been confirmed on hundreds of materials (i.e., essentially every metal where a sufficient degree of disorder could be experimentally achieved).[2,6,8,12,13]. Most remarkably, such apparent universality was found in the high-temperature regime, often extending to hundreds of Kelvin. The aim of this work is to propose, and validate against available experiments, an alternative scenario that can more plausibly explain the ubiquitous high-temperature anomalies identified by Mooij

Objectives

Results

Conclusion