Floquet Topological Polaritons in Semiconductor Microcavities

TL;DR

This paper models Floquet topological polaritons in semiconductor microcavities, demonstrating phase transitions and exotic insulator states driven by time-periodic potentials and field polarization control.

Contribution

It introduces a novel method to realize Floquet topological phases in polaritons using interference of coherent fields, revealing new topological states and phase transitions.

Findings

Realization of Chern insulator with weak fields

Observation of topological phase transition with increasing field strength

Identification of exotic flat band Chern insulator with unpaired Dirac cone

Abstract

We propose and model Floquet topological polaritons in semiconductor microcavities, using the interference of frequency detuned coherent fields to provide a time periodic potential. For arbitrarily weak field strength, where the Floquet frequency is larger than the relevant bandwidth of the system, a Chern insulator is obtained. As the field strength is increased, a topological phase transition is observed with an unpaired Dirac cone proclaiming the anomalous Floquet topological insulator. As the relevant bandwidth increases even further, an exotic Chern insulator with flat band is observed with unpaired Dirac cone at the second critical point. Considering the polariton spin degree of freedom, we find that the choice of field polarization allows oppositely polarized polaritons to either co-propagate or counter-propagate in chiral edge states.