Control and steering of integrated optical vortices.

Optical vortex beams carrying orbital angular momentum (OAM) have attracted considerable interest for applications in optical communication, sensing, and quantum information. Integrated photonics offers a compact and stable platform for their programmable controls. We demonstrate a fully integrated photonic circuit for the controllable generation, manipulation, and directional steering of azimuthally polarized vortex beams. Interference measurements confirm the controllable switching among five distinct OAM modes, identified by their topological charges. Vortex beam steering is achieved by reconfiguring phase profiles. This integrated platform provides a controllable and reliable solution for advanced OAM devices in free-space data transmission, quantum communication, and structured light steering, detection, and ranging.