Spin order and phase transitions in chains of polariton condensates

TL;DR

This study shows how coupled polariton condensates can be optically tuned to exhibit various spin-ordered phases, including a crossover phase, demonstrating a controllable non-equilibrium spin lattice.

Contribution

It introduces a method to control spin phases in chains of polariton condensates and reveals a crossover phase with alternating bonds, advancing understanding of non-equilibrium spin systems.

Findings

Demonstrated tunable spin phases from FM to AFM in 4-condensate chains

Identified a crossover phase with alternating FM-AFM bonds

Developed a scheme to prepare any desired spin state in larger chains

Abstract

We demonstrate that multiply-coupled spinor polariton condensates can be optically tuned through a sequence of spin-ordered phases by changing the coupling strength between nearest neighbors. For closed 4-condensate chains these phases span from ferromagnetic (FM) to antiferromagnetic (AFM), separated by an unexpected crossover phase. This crossover phase is composed of alternating FM-AFM bonds. For larger 8 condensate chains, we show the critical role of spatial inhomogeneities and demonstrate a scheme to overcome them and prepare any desired spin state. Our observations thus demonstrate a fully controllable non-equilibrium spin lattice.