介质柱型二维Triangular格子光子晶体的禁带特性

Band gap characteristics of two-dimensional photonic crystals made of a triangular lattice of dielectric rods

采用平面波展开法数值计算了空气背景中由圆形、正六边形和正方形介质柱构造的二维三角晶格光子晶体禁带结构,并研究了介质方柱旋转角度、介质折射率和填充比对完全光子禁带宽度的影响.结果表明,在低频区,介质方柱旋转17°时,出现最大完全光子禁带,且最大禁带宽度随介质折射率的变化较为稳定.在高频区,介质方柱旋转30°时,完全光子禁带宽度最大;且介质材料折射率n=2.2时即出现完全光子禁带,n=2.6时,完全光子禁带达到最大.

Plane wave expansion method is applied to simulate the bandgap of two-dimensional photonic crystals made of a triangular lattice of dielectric rods（circular,hexagon,square cross sections） in air.Moreover,the effect on band gap of a triangular lattice of square dielectric rods in air is discussed as a function of the rotation angle,the refractive index and the filling fraction,respectively.In the low frequency region,the maximum complete photonic band gap appears when the rotation angle equals 17 degrees.the maximum complete photonic band gap can be attained steadily as the refractive index changes continuously.In the high frequency region,the maximum complete photonic band gap appears when the rotation angle equals 30 degrees.The complete photonic band gap is observed when the refractive index is greater than 2.2.The width of complete photonic band gap reaches the maximum when the dielectric refractive index is equal to 2.6.