说明：  二维光子晶体禁带的MATLAB源码,光子晶体中因周期性结构而存在的频率禁带称为光子禁带，光子禁带的存在是光子晶体具有广泛应用前景的重要原因。 禁带越大，可控光的频带也越宽
(Two-dimensional photonic crystal band gap of MATLAB source, photonic crystal structure exists because of the cyclical frequency band known as photonic band gap, photonic band gap is the existence of photonic crystal has a broad application prospects of the important reasons. The greater the band gap, controllable light the more wide-band)