大带隙二维光子晶体结构的研究

Large Absolute Band Gaps of 2D Photonic Crystals

针对三种常见的介质柱横截面分别为正六边形,正方形和圆形的二维光子晶体,提出了一种增大光子带隙的方法.直角坐标系下,使X方向长度增大p倍,并以原点为中心旋转角度φ,通过调整p和φ来降低结构对称性,使用平面波展开法,对其进行了大量的仿真分析.结果表明,结构改变后的光子晶体具有较大的带隙率.对于三种介质柱的三角晶格结构的光子晶体,最大带隙率能达到12%以上,尤其对于正方柱三角晶格光子晶体,最大带隙率达到15.1%.

For three types of conventional 2D photonic crystals with medium column＇s cross sections＇ shapes of hexagon,square and circular,a method that decreases the length in X direction to be p times and rotates shapes with angle φ for increasing the PBG of the photonic crystals was brought forward. The symmetry of the structures were decreased through changing the values of p and φ. With simulation using planar wave expansion method,the results were show that max PBG rate can reach above 12%,due to the photonic crystals of the three types of medium column with triangular lattice. Especially for photonic crystals of rectangle column with triangular lattice,the max PBG rate arrives at 15.1%.