Quantum wire junctions breaking time reversal invariance

TL;DR

This paper investigates how to break time reversal symmetry at quantum wire junctions using the anyon Luttinger liquid model, providing a classification of critical points and their stability.

Contribution

It introduces a necessary and sufficient condition for breaking time reversal invariance based on the scattering matrix at the junction.

Findings

Identifies universal features of quantum wire junctions with broken time reversal symmetry.

Classifies critical points reachable by bosonization.

Analyzes stability and symmetry properties of these critical points.

Abstract

We explore the possibility to break time reversal invariance at the junction of quantum wires. The universal features in the bulk of the wires are described by the anyon Luttinger liquid. A simple necessary and sufficient condition for the breaking of time reversal invariance is formulated in terms of the scattering matrix at the junction. The phase diagram of a junction with generic number of wires is investigated in this framework. We give an explicit classification of those critical points which can be reached by bosonization and study the interplay between their stability and symmetry content.