通过对声子晶体负折射的实验和理论进行梳理,提出可以通过从对称性角度理解声波在周期性结构中的散射,来理解声学负折射现象的物理机制.在此启发下,本文继而运用有限元模拟,通过改变背景介质的声学常数,成功展示了声波在声子晶体中的负折射现象.
This paper briefly reviews both theoretical and experimental progress in negative refraction(NR) of phononic crystals,and suggests understanding the mechanism underlying the NR by studying the scattering of waves in periodical structures on the basis of the idea of symmetry.Then,based on a finite element approach,this paper shows the phenomena of NR by adjusting parameters of a host medium.