Spin rings in bi-stable planar semiconductor microcavities

TL;DR

This paper experimentally demonstrates spin bi-stability and the formation of controllable spin rings in exciton-polaritons within semiconductor microcavities, revealing detailed spin interactions at micrometer scales.

Contribution

It provides the first experimental observation of spin rings in exciton-polaritons and measures their interaction constants, advancing understanding of spin-dependent phenomena in microcavities.

Findings

Observation of spin rings with micrometer-scale control

Measurement of antiparallel polariton spin interaction constant

Confirmation of spin bi-stability in exciton-polaritons

Abstract

A unique feature of exciton-polaritons, inherited from their mixed light-matter origin, is the strongly spin-dependent polariton-polariton interaction, which has been predicted to result in the formation of spin rings in real space [Shelykh et al., Phys. Rev. Lett. 100, 116401 (2008)]. Here we experimentally demonstrate the spin bi-stability of exciton-polaritons in an InGaAs-based semiconductor microcavity under resonant optical pumping. We observe the formation of spin rings whose size can be finely controlled in a spatial scale down to the micrometer range, much smaller than the spot size. We additionally evaluate the sign and magnitude of the antiparallel polariton spin interaction constant.