声表面波在厚金属栅阵中的耦合模参数  

Coupling-of-modes parameters for surface acoustic waves propagating under metallic gratings with finite thickness

作　　者：徐方迁[1] 金步平[1] 

机构地区：[1]浙江传媒学院电子信息系,杭州310018

出　　处：《声学学报》2010年第4期441-445,共5页Acta Acustica

基　　金：国家自然科学基金(10974171);浙江省高等学校中青年学科带头人资助项目

摘　　要：提出了一种研究声表面波在压电晶体厚金属栅阵中传播特性的理论方法。将有限元和声表面波在周期栅阵中的变分原理分析方法相结合,在陈东培和H.A.Haus理论基础上、用有限元分析金属短路栅对声表面波传输特性的影响,将力学负载贡献的耦合模参数用有限元矩阵表示,使其适用于声表面波在厚金属或任意形状栅条中传输情况,给出了具体理论分析方法和相应的理论表达式。最后,具体研究了几种压电晶体上金、铝或银栅阵中声表面波的传输特性,通过数值计算给出了声表面波的耦合模参数。A theoretical method is presented in this paper,which analyzes properties of surface acoustic waves propagating on metallic gratings with finite thickness and combines a finite element method and a variational principle on surface acoustic waves propagating on periodic metal gratings.Based on D.P.Chen and Haus theory,a finite element method is used to investigate the effects of matallic gratings upon the propagation of surface acoustic waves.The coupling-of-modes parameters contributed by mechanical loading are expressed by the matrix derived from the finite element method.Consequently Chen and Haus theory can also be applied to analyze the properties of surface acoustic waves propagating on metallic gratings with finite thickness and arbitrary shape.Finally,the characteristics of surface acoustic waves propagating under gold and aluminium or silver gratings on a few piezoelectric crystals are studied. Numerical results of the coupling-of-modes parameters of the surface acoustic waves are obtained.

关 键 词：声表面波 金属栅 耦合模 有限元分析 传输特性 压电晶体 传播特性 变分原理 

分 类 号：O422[理学—声学]