The pseudo-spin dynamics of propagating exciton-polaritons in semiconductormicrocavities are known to be strongly influenced by TE-TM splitting. As avivid consequence, in the Rayleigh scattering regime, the TE-TM splitting givesrise to the optical spin Hall effect (OSHE). Much less is known about its rolein the nonlinear optical regime in which four-wave mixing for example allowsthe formation of spatial patterns in the polariton density, such that hexagonsand two-spot patterns are observable in the far field. Here we present adetailed analysis of spin-dependent four-wave mixing processes, by combiningthe (linear) physics of TE-TM splitting with spin-dependent nonlinearprocesses, i.e., exciton-exciton interaction and fermionic phase-space filling.Our combined theoretical and experimental study elucidates the complex physicsof the four-wave mixing processes that govern polarization and orientation ofoff-axis modes.
展开▼
