利用传输矩阵法理论,通过数值计算模拟的方法,研究双负介质对一维光子晶体透射能带谱的影响。结果表明:当C介质由双正介质变成双负介质时,光子晶体(CBAABC)n的禁带、能带和光子晶体(AB)m(CBAABC)n(BA)m的透射峰均出现明显的简并现象,即前者相邻多禁带和多能带结构简并为较宽的单禁带和单能带结构,后者的透射峰由2n+1条简并成2n-1条;当双负介质C的光学厚度负值减小时,光子晶体(AB)m(CBAABC)n(BA)m的透射峰向禁带中心靠拢,出现简并趋势。双负介质对光子晶体透射能带谱的简并效应,为光子晶体设计光学滤波器件、光学开关等提供参考。
The degeneracy effect of double negative medium on the transmission spectrum band of one-dimensional photonic crystal is studied with transfer matrix theory and computational simulation method. The results show that, when the double negative medium C is changed into one of double positive medium, the degeneracy is appeared on the band gap and transmission band of photonic crystal (CBAABC)m and the transmission peak of photonic crystal (AB)m (CBAABC)n(BA)m, so as the first case, the adjacent multiple band gaps and transmission bands are combined into one band gap and one transmission band, and the second case, 2n+ 1 transmission peaks also are combined into 2n-1 peaks. When the decreasing optical thickness of negative medium C, the transmission peaks is close to the center of photonic crystal (AB)m (CBAAC)n (BA)m band-gap and tend to degenerate. The degeneracy effect of the double negative medium on photonic crystal can provide reference for design of optical filter devices and optical switches.