基于二维声子晶体的选频选向加权声波导  

A Frequency-selecting and Direction-selecting Weighting Waveguide Based on Two-dimensional Phononic Crystals

作　　者：田亚会[1] 李红浪[1] 袁策[1,2] 柯亚兵 何世堂[1] 

机构地区：[1]中国科学院声学研究所,北京100190 [2]北京理工大学,北京100081

出　　处：《人工晶体学报》2016年第3期604-611,共8页Journal of Synthetic Crystals

基　　金：国家自然科学基金(11174318;11304346);国家高技术研究发展计划(863计划)(SS2013AA041103);北京市科委项目(Z141100003814016)

摘　　要：本文提出一种基于二维压电声子晶体的声表面波选频选向加权声波导,即在垂直的两个方向上具有不同的晶格常数。为分析其特性,以空气孔/128°YX铌酸锂声子晶体为例,采用有限元方法并结合纵向深度上位移场的分布特点提取出表面波模态,同时采用P矩阵模型和三维有限元方法分析了ΓX和ΓY方向上的传输系数,进一步提取出位移场的传播分布。结果具有很好一致性,同时显示不同晶格加权结构,在特定频段上实现一个方向带通而另一个方向带阻,即具有选频选向的声波导特性,证实了提出的选频选向加权声波导的可行性。This paper has proposed a frequency-selecting and direction-selecting weighting waveguide of surface acoustic wave( SAW),which has different lattice constants in two directions of phononic crystals( Pn Cs). To study the property of it,as an example,weighting waveguide based on two-dimensional( 2-D) air /128°YX Li Nb O3 piezoelectric Pn Cs was used to analyze in this paper. First the band structures were analyzed using the finite element model( FEM) and SAW modes were extracted based on the displacement distribution in depth. Then based on the P matrix analysis and three-dimensional FEM,transmissions in directions of ΓX and ΓY were calculated. Furthermore,displacements distributions of propagating were extracted. Results are consistent and show different weighting waveguide can prohibit the waves in one direction while permit the waves in another direction. This means that the weighting waveguide has the property of selecting frequency and direction. This study verifies the practicable of the frequency-selecting and direction-selecting weighting waveguide.

关 键 词：压电声子晶体 声表面波 加权声波导 

分 类 号：O735[理学—晶体学]