All-optical NOT and XOR logic gates using photonic crystal nano-resonator and based on an interference effect

Abstract

In this study, a small size, low power, simple and high contrast ratio (CR) structure was designed and simulated to use in photonic crystal-based all-optical logic gates. This structure can be used for both all-optical logic NOT and XOR gates. The suggested structure is composed of three waveguides and a nano-resonator. The nano-resonator was designed by removing two dielectric rods. For use as an optical NOT logic gate, one of the input ports enters the control signal. In this case, the CR between logic levels '0' and '1' is 20.53 dB, which is higher than that of the provided gates based on structures published recently. The CR for the XOR gate is 19.95 dB. The response time to the input signal of the designed gate is 0.466 ps. The simplicity of the structure, small size, and high CR are the advantages of this structure compared to previously provided logic gates. The results have proven a superior prospect for the proposed structure to use in all optical integrated circuits.