Tunable Vector Vortex Beam Vertical Cavity Surface Emitting Laser
Yuanfei Hui, Le Zhou, Yuanfeng Liu, Zhao‐Yv Luan, Qianhui Sun, H. Wang, Jingbo Sun, Baolu Guan
Abstract
Abstract Light source with Orbital Angular Momentum lasing is critical in future optical communications and optical manipulation. However, vector vortex beam laser light sources face challenges in miniaturization, untunable, and the complexity of fabrication processes. In this study, an ultra‐compact scheme of a tunable vector vortex vertical cavity surface emitting laser is proposed that is tunable in both polarizations and topological charges. Cholesteric liquid crystals and spherulites are integrated into a vertical‐cavity surface‐emitting laser to generate a vector vortex beam. The cholesteric liquid crystals first load the spin angular momentum, which is then converted into orbital angular momentum by the spherulite, and finally enable the vector vortex beam emission. By introducing molecular motors, the optical vortex topological charge number can be freely switched between –1 and +1 under UV illumination. Based on the fascinating optical activity of liquid crystals, the prepared laser can also be controlled to emit a Hermite–Gaussian mode beam with polarization angles from – 44° to + 44°. This chip‐scale tunable vector vortex beam laser can be useful in the field of optical manipulation, quantum encryption, and optical communication fields.