One-dimensional Photonic Crystal with Large Band Gaps Designed by Annealing-Genetic Algorithm
基于像素法用模拟退火-遗传算法搜索一维宽带隙光子晶体

An annealing algorithm,a genetic algorithm,and a hybrid algorithm of Annealing algorithm and genetic algorithm are used to design a one-dimensional photonic crystal with the maximal band gap(difined as the gap to midgap ratio).The unit cell is divided equally into many pixels,and each filling pattern of pixels with two dielectric materials corresponds to a chromosome consisting of binary digits 0 and 1.Starting from randomly generated photonic crystal,the evolutionary algorithms yielded a photonic crystal with maximal band gap.Two structures are found with large band gaps,one is a structure of unit cell of two layers with band gap 43.76% ,the other is a structure of unit cell of four layers with band gap 43.53%.It is discovered that the band gap is not sensitive to the thickness of each layer of unit cell,but increases with the increase of the index difference of two dielectrics.