Polariton pillar cavity: polarization, interactions, correlations

Olivier Bleu

We investigate theoretically exciton-polariton correlations in a resonantly driven pillar cavity embedding a 2D semiconductor layer accounting for the polarization degree of freedom.  We show that the different interaction strengths between co- and counter-circularly polarized polaritons and an eventual linear birefringence can give rise to a rich phenomenology.

We obtain analytical results for the steady-state polarization resolved polariton populations and second-order coherence functions, for the cases where the laser drive is circularly polarized or linearly polarized, which capture the essential features of the numerical results obtained using a Lindblad master equation. Notably, we highlight that depending on the excitation drive polarization, both the conventional and unconventional regime of antibunchings can be investigated in a single pillar cavity. We also unveil the importance of the singlet (interspin) polariton-polariton interactions whose sign and strength can be experimentally controlled [1, 2]. We argue that a large singlet interaction could explain the relatively strong nonlinearities reported in two recent experiments with single GaAs quantum-well cavities [3, 4].

Our results have implications for the experimental investigations of the polariton blockade effect and interaction mediated photon quantum correlations in these systems. In practice, existing open-cavities with embedded atomically-thin semiconductors appear as promising platforms to precisely investigate these effects.