High-speed directly-modulated cylindrical vector beam lasers

Cylindrical vector (CV) beams are highly desirable for wide applications ranging from manipulation to communications. Despite diverse schemes of CV beam emitters, the efficient generation of vector beams by active photonic integrated devices, especially for direct modulation, is still an outstanding challenge. Here, we report the first high-speed directly modulated CV beam laser under electrical pumping. InP-based microring cavities with two sets of optimized second-order gratings enable single-mode lasing and efficient emission assisted by ion implantation. The high-differential-gain multiple-quantum-well structure and small active region benefit high-speed modulation. The surface emission facilitates easy 2D array integration. CV beam lasing is achieved with >1 mW output power and ∼50 dB side-mode suppression ratio (SMSR). CV beam lasers at 8–20 Gbit/s are realized in the experiment. Moreover, a 2 km fiber vector eigenmode transmission link, seeded by a 10 Gbit/s directly modulated CV beam laser, is als...