一种光子晶体滤波器的设计

Design of a Photonic Crystal Filter

设计了一种由TiO2和SiO2两种介质构成的对称式光子晶体,并在考虑色散关系的基础上,利用传输矩阵法,计算了该光子晶体的透射谱。结果表明：当入射角θ≤30°时,在0.8~1.2ν/ν0的频率范围内只有一个半宽度较窄、透射率为1的透射峰。入射角增加,透射峰中心频率发生蓝移,峰值保持不变,半宽度变化很小。与之对应的光子晶体滤波器具有极好的透射性、良好的单色性和较好的角度宽容性,特别适合小角度入射的情况。

A symmetric photonic crystal composed of TiO2 and SiO2 was designed,and its transmission spectrum was calculated with the method of transfer matrix by taking consideration of the dispersion relation.The results indicate that there is only one transmission peak with narrow half-width and the transmission rate value of 1in the frequency range of 0.8~1.2ν/ν0.When the incident angle increases,the center frequency of the transmission peak will present blue-shift with constant peak value and basically invariable half-width.Thus the corresponding photonic crystal filter has excellent transmittance,good monochromaticity and better angle tolerance,therefore it is more suitable with the situations with small angle of incidence.