High bandwidth SOI photonic wire ring resonators using MMI couplers.

A ring resonator in SOI photonic wire waveguides is demonstrated using a compact MMI coupler with 3mum x 9 mum footprint as the coupling element. We achieved high bandwidth of 0.25 nm, and a quality factor Q of ~ 6000 for rings with a radius of 50 mum. Unlike directional coupler based rings, these resonators have a wavelength independent Q and extinction ratio over more than 30 nm wavelength range, and there is no loss penalty for increasing …