Nonequilibrium spinor exciton-polariton condensates in a magnetic field

Abstract

A complete-nonequilibrium model is proposed to investigate spinor exciton-polariton condensates (SEPCs) in a magnetic field. Due to the Zeeman splitting (ZS), the loss rates of two spin components in a magnetic field are distinct and affected by the magnetic field. Therefore, the individual spin component of a SEPC has its own threshold pump power. We investigate the ZS and degree of circular polarization of the SEPC as a function of the excitation power and magnetic field. Above both spin-dependent threshold pump powers, we find an increasing degree of circular polarization with the magnetic field and a quenching of the ZS below a critical strength of the magnetic field. The ZS of a SEPC shows a reverse sign and its magnitude is increasing significantly compared to the uncondensed exciton-polartion ZS. The effect of a magnetic field on excitation spectra of SEPCs are also investigated. We find that the excitation dispersions are Bogoliubov excitations if the pump power is low. The nonequilibrium fluctuations in a SEPC are reduced when a magnetic field is applied.