采用传输矩阵法理论,通过模拟仿真的方式,研究不对称度对一维三元对称结构光子晶体(C_mA_mB_m)~n(B_mA_mC_m)~n透射特性的影响,结果表明:当光子晶体处于镜像对称结构(CAB)~n(BAC)~n时,透射谱的禁带中出现的单条透射峰随周期数n增大而变精细,但透射峰的透射率及所处的波长位置不变。当光子晶体对称性受到破坏时,随着周期不对称度Δn增大,透射谱中单透射峰的透射率快速下降,但所处的波长位置不变;随着A、B、C介质层厚度不对称度增大,透射谱中单透射峰的透射率出现不同程度的下降,并向波长方向蓝移。其中A、B、C介质层厚度不对称度同时增大时,透射率下降及蓝移速度最快,A层介质不对称度Δd_A增大时透射率下降速度次之。不对称度对一维三元对称结构光子晶体透射特性的作用机制,为光学滤波、光学开关及全反射器件等的研究和设计提供理论指导。
The effect of asymmetric on the transmission properties of one-dimensional temary photonic crystal(C_mA_mB_m)~n(B_mA_mC_m)~nis studied by transfer matrix theory and numerical simulation method. The result shows that when the photonic crystal is a mirror symmetrical structure(CAB)~n(BAC)~n, the single transmission peak in the band of spectrum becomes fine with increase of cycle number n, but the transmittance and the wavelength position of transmission peak are unchanged. When the symmetry of the photonic crystal is destroyed, the transmittance of single peak is decrease rapidly, but the wavelength position of transmission peak is constant. The transmittance of single peak is decreasing in varying degrees with increase of asymmetry of the thickness of A, B or C medium layer, and the wavelength position of transmission peak is shifting to long wave direction. However, when the asymmetry of the thickness of A, B and C medium layer are increased at the same time, the transmittance of peak is decreasing and the position of peak is fast blue-shift. The effect mechanism of asymmetry on the transmission properties of One-dimensional temary photonic crystal can provide the theoretical guidance for research and design of optical filter, optical switch and total reflection device.