Dual band gaps optimization for a two-dimensional phoxonic crystal

Abstract A two-dimensional phoxonic crystal (PxC) with optimal dual phononic and photonic complete band gaps (BGs) is proposed and analyzed numerically. Using finite element simulations, the thickness of the frame and the length of square silicon as well as the length of the square scatterer are found to be the three key factors influencing the dual BGs of PxC. Based on the orthogonal test design, 3-factor and 5-level experiments are designed to determine the relationships between the total bandwidths of the photonic and phononic BGs, respectively, with the three key factors. Using the two functional relationships as the unified objective function, the optimal thickness of the frame, and the length of square silicon and square scatterer are obtained to open the optimal dual BGs of PxC. It is expected that the combination of orthogonal test design and finite element simulations is a helpful way to design PxCs.