Aharonov-Bohm caging in spin-orbit coupled exciton-polariton lattices

TL;DR

This paper explores how the Aharonov-Bohm caging effect in exciton-polariton lattices can be controlled via spin-orbit coupling and lattice geometry, affecting energy bands and polariton transport, with implications for trapping and steering polaritons.

Contribution

It introduces a method to control AB caging in exciton-polariton lattices through RDSOC and lattice design, including effects of non-Hermitian dynamics and disorder.

Findings

AB caging is influenced by RDSOC orientation and lattice geometry.

Disorder causes inverse Anderson localization in the system.

AB caging can be switched on and off using external voltage in microcavities.

Abstract

We study the Aharonov-Bohm (AB) caging effect in rhombic exciton-polariton lattices, with the Rashba-Dresselhaus spin-orbit coupling (RDSOC) in acting a synthetic gauge field. The effective magnetic flux through each plaquette is controlled by the orientation of the RDSOC and geometry of the rhombic lattice. The results show that the interplay of lattice geometry and the RDSOC will dramatically influence the energy band structure, furthermore, determining the transportation properties of exciton-polariton condensates. Non-Hermitian effects, which arise from the polariton intrinsic loss mechanism, on the AB caging is also discussed in detail. Meanwhile, the effect of disorder on the dynamics of AB caging is investigated, and we find that the disorder will lead to the inverse Anderson localization. We propose that using the AB caging effect allows to trap and steer the propagation of polaritons in a given parameter regime. Considering the specific example of a photonic liquid crystal microcavity to achieve our theoretical predictions, the AB caging could be switched on and off by applying an external voltage.