Low-threshold photonic crystal all-optical switch using plasmonic nanowires placed in nonlinear resonator structure

We propose a tunable, all-optical switch based on nonlinear photonic crystal ring resonators. Arrays of silver nanowires are embedded in the ring resonator to enhance the nonlinearity. Due to surface plasmon resonance and plasmonic field enhancement in the regions of metallic nanowires, the light intensity required for the operation of the proposed switch is reduced significantly. The minimum time and threshold power required to turn the switch on/off are ∼0.34 ps and 85 mW/μm2, respectively. The performance of the proposed switching structure is simulated by the finite-difference time-domain method in which the simulations indicate an ultracompact size structure with a promising ultrafast speed.