Residual bulk viscosity of a disordered 2D electron gas

TL;DR

This paper demonstrates that disorder in a 2D noninteracting electron gas under a magnetic field causes a nonzero residual bulk viscosity, providing insights into scale invariance breaking and bounds for interacting systems.

Contribution

It derives an analytic expression for residual bulk viscosity in disordered 2D electron gases using the self-consistent Born approximation, highlighting its fundamental role.

Findings

Disorder induces nonzero bulk viscosity in 2D electron gases.

Residual bulk viscosity sets a lower bound for interacting systems.

Analytic expression derived within the self-consistent Born approximation.

Abstract

The nonzero bulk viscosity signals breaking of the scale invariance. We demonstrate that a disorder in two-dimensional noninteracting electron gas in a perpendicular magnetic field results in the nonzero disorder-averaged bulk viscosity. We derive analytic expression for the bulk viscosity within the self-consistent Born approximation. This residual bulk viscosity provides the lower bound for the bulk viscosity of 2D interacting electrons at low enough temperatures.