Author:
Cheng Lirong,Mao Simei,Chen Houyu,Li Qian,Fu H. Y.
Abstract
We propose a compact Si3N4-Si3N4-SOI grating coupler for generating optical vortex beams. With various mode input combinations, the multi-layer device can be tuned to emit beam with OAM states of ± 1 and ± 2.