Ring Resonator Coupled M-z All-optical Switch by Using a Pumped Nonlinear Directional Coupler

Abstract – We propose a new ring resonator side-coupled M-Z interferometer all-optical switch through the pumped nonlinear directional coupler. By controlling pump power P to lead the coupler reflectivity r approaching to 1, the resonator finesse will be enhanced dramatically, and then the minimum switching power in silica-based practice devices can be obtained. As a sample, we use a nonlinear coupler made by two erbium-doped fibers, and launch a 514.5nm-pump light into one of the cores to make the reflectiveindex difference between two cores. Based on the asymmetric-coupler theory, we simulate the relationship between r and P , and show that the required pump power is only 0.8mW for 1 r → .