Polarization Independent Grating in GaN-on-Sapphire Photonic Integrated Circuit

In this work, we report the realization of a polarization-insensitive grating coupler, single-mode waveguide, and ring resonator in GaN-on-Sapphire platform. We provide detailed demonstration material characterization, device simulation, experimental results. achieve coupler efficiency -5.2 dB/coupler with 1dB 3dB bandwidth 40 nm 80 nm, respectively. measure waveguide loss -6 dB/cm. The losses measured here are lowest photonic circuit. This provides opportunities for development on-chip linear non-linear optical processes using To best our knowledge, is first an integrated GaN HEMT stack 2D electron gas.