Time-Reversal Symmetry Breaking and Decoherence in Chaotic Dirac Billiards

TL;DR

This paper investigates how dephasing mechanisms influence the transition from quantum to semiclassical behavior in chaotic Dirac billiards, highlighting the effects of symmetry breaking and crossover fields.

Contribution

It provides a comprehensive statistical analysis of Dirac billiards under dephasing, emphasizing the impact of symmetry crossover fields on conductance and regime transition.

Findings

Dephasing mechanisms drive the transition from quantum to semiclassical regimes.

Finite crossover fields significantly affect conductance towards the unitary ensemble limit.

Dirac billiards exhibit a rapid shift from quantum to semiclassical behavior due to dephasing.

Abstract

In this work, we perform a statistical study on Dirac Billiards in the extreme quantum limit (a single open channel on the leads). Our numerical analysis uses a large ensemble of random matrices and demonstrates the preponderant role of dephasing mechanisms in such chaotic billiards. Physical implementations of these billiards range from quantum dots of graphene to topological insulators structures. We show, in particular, that the role of finite crossover fields between the universal symmetries quickly leaves the conductance to the asymptotic limit of unitary ensembles. Furthermore, we show that the dephasing mechanisms strikingly lead Dirac billiards from the extreme quantum regime to the semiclassical Gaussian regime.