Conversion of Spin‐Orbit‐Coupled Optical Vortices via Complex Coupling

Optical vortices provide an additional freedom because of the orbital angular momentum (OAM), enabling significant advances in high‐dimensional information encoding, quantum communication, and super‐resolution imaging. However, the controlled conversion between spin‐orbit‐coupled (SOC) optical vortices of different orders remains challenging. Here, we propose a novel four‐step Floquet driving protocol governed by complex coupling to realize conversion between distinct angular momentum characteristics in strongly confined waveguide arrays. Optical vortices naturally give rise to complex‐valued coupling coefficients owing to their intrinsic spatial‐phase structure and spin–orbit interaction. Building on this mechanism, we implement a Floquet driving protocol in the waveguide array, which supports corner and edge states determined by the coupling parameters. Exploiting the corner states, we demonstrate dynamic conversion of total‐angular‐momentum order from to across successive two or three driving periods. This work opens a pathway toward dynamic modulation of structured light and advances the integration of OAM‐based functionalities in photonic platforms.