Dissipative Quantum Criticality as a Source of Strange Metal Behavior

The strange metal behavior, usually characterized by a linear-in-temperature ( T) resistivity, is a still unsolved mystery in solid-state physics. It is often associated with the proximity to a quantum critical point (a second order transition at temperature T = 0, leading to a broken symmetry phase) 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 electron density diffusive modes that accounts both for the linear-in-T resistivity and for the logarithmic specific heat versus temperature ratio C-V/T similar to log(1/T), down to low temperatures.

Automated summary

The strange metal behavior, characterized by linear-in-temperature resistivity, is still a mystery in solid-state physics. It is often associated with a quantum critical point and the divergence of order parameter correlation length. This study proposes a paradigm shift, focusing on a divergent characteristic time scale due to divergent dissipation in critical modes, while their correlation length remains finite. A mechanism based on the coupling between local order parameter fluctuations and electron density diffusive modes is proposed to explain the linear-in-T resistivity and logarithmic specific heat versus temperature ratio down to low temperatures.