Emergence of Rashba Spin‐Orbit Coupling in Staggered‐Gyromagnetic Photonic Crystals

ABSTRACT We report the emergence of Rashba spin–orbit coupling (SOC) in a 2D staggered‐gyromagnetic photonic crystal under a uniform out‐of‐plane DC magnetic bias arrangement in a modified honeycomb lattice. The system exhibits a Mexican‐hat‐like band structure and helical spin textures, which are the major characteristics of Rashba SOC. Through both full‐wave simulations and k ‐ p theory, we confirm the emergence of spin‐split bands and vortex‐like spin textures centered at the Brillouin zone. In addition, the two Rashba branches exhibit spin‐momentum locking, so that a normally incident beam splits into two spin‐resolved channels propagating in divergent directions. These results establish a platform for exploring Rashba SOC in photonics and spin‐controlled wave transport in periodic systems.