We report both optical and electrical generation of spin-polarized exciton-polaritons in a monolithic MAPbI3 perovskite metasurface integrated into a light-emitting transistor (LET). The metasurface supports high-Q bound state in the continuum (BIC) resonances, which strongly couple to the perovskite excitons, enabling polariton condensation at threshold excitation fluence. The Rashba-split polariton LET emission shows momentum-entangled dispersion branches within the same mode, which can be electrically addressed by group velocity selection. These results demonstrate the feasibility of using polycrystalline perovskite metasurfaces for high-purity, electrically controlled spin-polarized polaritons and condensates – without the need for external magnetic fields or synthetic gauge potentials.
