弹性波在一维掺杂声子晶体中的多缺陷模特征

推导出弹性波在一维掺杂声子晶体中的转移矩阵,研究了弹性波在一维掺杂声子晶体中的缺陷模特征。得出:弹性波在一维掺杂声子晶体中会出现多个缺陷模。缺陷模的数目随杂质厚度的增加而增加,缺陷模的半高宽随缺陷模数目的增加而减小。缺陷模的数目也随杂质声阻抗的增加而发生变化,各缺陷模的位置随杂质声阻抗的增加向禁带中心移动。这些特性可以作为设计多通道弹性波滤波器的理论依据。

Many-Defect-Mode Characteristic of Flexible Wave in 1-D Doping Phononic Crystal

The transfer matrix of flexible wave in 1-D doping phononic crystal is derived.The defect mode characteristic of flexible wave is studied.Results show that in 1-D doping phononic crystal there are many defect-modes of flexible wave.The number of the defect modes increase with the increase of the thickness of the impurity,the full-width at half maximum of the defect mode reduces with the increase of the number of the defect-mode.The number of the defect-mode increases with the increase of the sound impedance of the impurity.The position of the defect mode moves toward the center when the sound impedance of the impurity increases.These characteristics of defect mode form the theoretical basis for designing a photonic crystal filter.