采用时域有限差分(FDTD)法计算了含色散介质一维光子晶体微腔的透射谱,研究了缺陷模的频移特性。通过与无色散光子晶体微腔透射谱相比较,发现了介质色散导致的缺陷模频移现象,并详细地分析了中心频率、色散强度和衰减系数等色散介质参量和缺陷模频移的依赖关系。模拟结果显示,缺陷模的频移决定于中心频率、色散强度和衰减系数等色散介质参量的大小,通过合理的调节这些参量,可以有效地调节缺陷模的频率。

Transmission spectrum of a one-dimensional photonic crystal micro-cavity containing dispersive medium are calculated by use of the finite-difference time-domain method, and frequency shift of defect modes is investigated. In comparison with photonic crystal without dispersive medium inside micro-cavity, we find the frequency shift phenomenon of defect modes which results from the medium dispersion. And then, the dependence of frequency shift of defect modes on dispersive medium parameters such as strength of dispersive, damping coefficient and centre frequency is analyzed in detail. The result shows that the above parameters of dispersive medium determine the resonant frequency of the defect modes. The frequency of the defect modes can be significantly tuned by adjusting carefully the dispersive medium parameters. Such phenomenon can be used to tune the resonant frequency, which has a great potential for a new generation of optical components.