Convection cells induced by spontaneous symmetry breaking

TL;DR

This paper demonstrates the emergence of convection cells driven solely by temperature gradients in a simple non-equilibrium system, specifically an Ising lattice gas, highlighting spontaneous symmetry breaking as the underlying mechanism.

Contribution

It reveals the existence of convection cells in a minimal system with only a temperature gradient, driven by spontaneous symmetry breaking, expanding understanding of non-equilibrium phenomena.

Findings

Convection cells appear below the critical temperature.

Spontaneous symmetry breaking drives convection in the system.

The phenomenon occurs in a simple lattice gas model.

Abstract

Ubiquitous in nature, convection cells are a clear signature of systems out-of-equilibrium. Typically, they are driven by external forces, like gravity (in combination with temperature gradients) or shear. In this article, we show the existence of such cells in possibly the simplest system, one that involves only a temperature gradient. In particular, we consider an Ising lattice gas on a square lattice, in contact with two thermal reservoirs, one at infinite temperature and another at $T$. When this system settles into a non-equilibrium stationary state, many interesting phenomena exist. One of these is the emergence of convection cells, driven by spontaneous symmetry breaking when $T$ is set below the critical temperature.