Nonequilibrium transitions, chaos, and chimera states in exciton-polariton systems
S.S. Gavrilova,b aInstitute of Solid-State Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region, Russian Federation bNational Research University Higher School of Economics, ul. Myasnitskaya 20, Moscow, 101000, Russian Federation
The review is devoted to exciton polaritons, short-lived Bose particles which are optically excited in semiconductors and form macroscopically coherent states under the conditions of coherent and resonant external driving. Interaction of polaritons results in multistability, spontaneous breaking of spin and spatial symmetries, self-pulsations, and pattern formation. In contrast to conservative systems, where broken-symmetry states are usually steady and characterized by a small number of order parameters, the polariton system also features paradoxical "chimera states" in which order and chaos coexist and in some way balance each other.