基于平面波算法的二维正方点阵声子晶体禁带研究

声子晶体能够产生完全的弹性波禁带，可以阻止声波或者振动在其内部传播。采用平面波算法研究了二维正方点阵声子晶体的禁带结构。在甲醇／水银双组分二维（2D）液相体系中发现了很大的完全禁带，到目前为止，在固相体系和其他液相体系中还没有发现相同宽度和相同数量的完全禁带。还研究了声子晶体中散射体的横截面为圆形和绕其中心轴旋转任意角度的正方形时完全禁带的产生规律，探索了第一禁带宽度与第一禁带中心频率的比值△Ω1/Ωc1和填充率F之间的关系，以及前50个频带中禁带的总宽度∑△Ωn/Ωcn和填充率F之间的关系。

A Study of Band Gap for Two Dimensional Phononic Crystal with Square Lattices Based on Plane Wave Algorithm

Phononic crystal can give rise to complete acoustic band gaps within which sound and vibrations are forbidden. In this paper, we use plane wave algorithm to study the band gap structure of 2D phononic crystal with square lattices. The results show that a giant full band gap is found in the CH3OH /Hg system. And in other solid or liquid system, the same width and quantity full band gaps have not been found so far. The influence of different cross section shapes of the scatter pole in 2D phononic crystal for forming full band gap is also studied. From the results, we get the relation of the first(total) relative frequency width with the filling ratio.