介绍一种方法来调节和优化二维光子晶体不同能带之间的带隙.在单胞中任意位置增加一个基元,可以调节不同能带之间的带隙.而且固定两个基元的最佳位置,调节两个基元柱体边长,可以找到一个合适的配置,使各自的带隙相对带宽达到更大值.同时结果也表明双基元情况下,不同能带之间带隙优化对系统对称性要求不同,频率越高处的带隙优化要求系统对称性越低.
A method is introduced to tune and optimize the photonic band gaps (PBGs) of two-dimensional photonic crystals (PCs). PBGs between the bands at low frequency can be tuned by an additional atom rod at arbitrary positions. Moreover, fixing up the two atom rods at optimal positions and tuning the lengths of the two cylinders, the normalized gap widths of PBGs could be enlarged with a suitable configuration. The results also show that the setting up of large PBGs depends on different degrees of symmetry of the system in the case of two atom rods in a unit cell, the larger PBGs at higher frequency require lower symmetry.