Non-Abelian chiral symmetry controls random scattering in two-band models

TL;DR

This paper investigates how non-Abelian chiral symmetry influences quantum particle dynamics in two-band models with disorder, revealing persistent symmetry effects even after symmetry breaking.

Contribution

It demonstrates that non-Abelian chiral symmetry continues to govern dynamics despite potential-induced symmetry breaking, and explores spontaneous symmetry breaking via a self-consistent method.

Findings

Quantum dynamics remain controlled by non-Abelian chiral symmetry after symmetry breaking.

Spontaneous symmetry breaking is analyzed and potential instabilities are discussed.

The study provides insights into symmetry effects in disordered two-band quantum systems.

Abstract

We study the dynamics of non-interacting quantum particles with two bands in the presence of random scattering. The two bands are associated with a chiral symmetry. After breaking the latter by a potential, we still find that the quantum dynamics is controlled by a non-Abelian chiral symmetry. The possibility of spontaneous symmetry breaking is analyzed within a self-consistent approach, and the instability of a symmetric solution is discussed.