Optical spin Hall effect driven by hybrid spin-orbit coupling in organic microcavities.

The optical spin Hall effect (OSHE) bridges photonics and spintronics by enabling spin-dependent manipulation of light-where the "spin" of light refers to its polarization state-which is critical for on-chip photonic technologies. While OSHE with distinct topological textures has been demonstrated separately using transverse electric-transverse magnetic (TE-TM) splitting or birefringent crystals, achieving multiple spin textures within a single system remains elusive. Here, we report the first observation of OSHE driven by the interplay between TE-TM splitting and Rashba-Dresselhaus spin-orbit coupling (RDSOC) in an organic microcavity at room temperature. Polarization-resolved measurements reveal hybrid spin textures: quadrupole patterns at high momenta from TE-TM splitting and mirror-symmetric textures at low momenta from RDSOC. This interplay generates a persistent spin bias with a polarization lifetime of ∼300 ps, indicating robust spin coherence for stable spin-photonic and polarization-preserving devices. Our findings establish organic microcavities as versatile platforms for engineering hybrid spin-orbit coupling, advancing topological photonics and integrated spin-based information processing.