# Asymmetry of non-local dissipation: From drift-diffusion to hydrodynamics

## TL;DR

This paper investigates how dissipation and heat distribution in two-dimensional electron systems differ between hydrodynamic and impurity-dominated regimes, revealing asymmetries in heat profiles that can be experimentally distinguished.

## Contribution

It predicts a current-induced asymmetry in heat distribution in the hydrodynamic limit and contrasts it with impurity-dominated heating, providing a method to differentiate these regimes experimentally.

## Key findings

- Hydrodynamic dissipation profiles are asymmetric and controllable by the driving field.
- Impurity-dominated heating remains symmetric and field-independent.
- Results align with recent experimental observations in narrow constrictions.

## Abstract

We study dissipation in inhomogeneous two-dimensional electron systems. We predict a relatively strong current-induced spatial asymmetry in the heating of the electron and phonon systems -- even if the inhomogeneity responsible for the electrical resistance is symmetric with respect to the current direction. We also show that the heat distributions in the hydrodynamic and impurity-dominated limits are essentially different. In particular, within a wide, experimentally relevant interval of driving fields, the dissipation profile in the hydrodynamic limit turns out to be asymmetric, and the characteristic spatial scale of the temperature distribution can be controlled by the driving field. By contrast, in the same range of parameters, impurity-dominated heating is almost symmetric, with the size of the dissipation region being independent of the field. This allows one to distinguish experimentally the hydrodynamic and impurity-dominated limits. Our results are consistent with recent experimental findings on transport and dissipation in narrow constrictions and quantum point contacts.