Spontaneous and Superfluid Chiral Edge States in Exciton-Polariton Condensates

TL;DR

This paper proposes a method to create topological band structures in exciton-polariton condensates through interactions, enabling spontaneous topological transitions and superfluidity without external magnetic fields.

Contribution

It introduces a novel scheme for engineering topological gaps in polariton systems using spin anisotropy, avoiding the need for magnetic fields or strong spin-orbit coupling.

Findings

Spontaneous topological transitions occur during polariton condensation.

Topological dispersion can be engineered under resonant coherent pumping.

The system exhibits properties associated with polariton superfluidity.

Abstract

We present a scheme of interaction-induced topological bandstructures based on the spin anisotropy of exciton-polaritons in semiconductor microcavities. We predict theoretically that this scheme allows the engineering of topological gaps, without requiring a magnetic field or strong spin-orbit interaction (transverse electric-transverse magnetic splitting). Under non-resonant pumping, we find that an initially topologically trivial system undergoes a topological transition upon the spontaneous breaking of phase symmetry associated with polariton condensation. Under resonant coherent pumping, we find that it is also possible to engineer a topological dispersion that is linear in wavevector -- a property associated with polariton superfluidity.