Disorder-driven dissipative quantum criticality as a source of strange metal behavior

TL;DR

This paper proposes a new mechanism for strange metal behavior, attributing it to disorder-driven divergent dissipation affecting critical modes, rather than traditional quantum critical point divergence.

Contribution

It introduces a paradigm shift by focusing on divergent dissipation rather than correlation length, explaining linear resistivity and specific heat behavior in strange metals.

Findings

Divergent dissipation explains linear-in-T resistivity.

Coupling between local order and electronic modes accounts for observed thermodynamic properties.

Finite correlation length with divergent dissipation challenges traditional quantum criticality models.

Abstract

The strange metal behavior, usually characterized by a linear-in-temperature (T) resistivity, is a still unsolved mystery in solid-state physics. Usually it is associated with the proximity to a quantum critical point (a second order transition at temperature T = 0) focusing on the related divergent order parameter correlation length. Here, we propose a paradigmatic shift, focusing on a divergent characteristic time scale due to a divergent dissipation acting on the fluctuating critical modes, while their correlation length stays finite. To achieve a divergent dissipation, we propose a mechanism based on the coupling between a local order parameter fluctuation and electronic diffusive modes, that accounts both for the linear-in-T resistivity and for the logarithmic specific heat versus temperature ratio C_V/T ~ log(1/T), down to low temperatures.