材料吸收对一维掺杂声子晶体禁带和缺陷模的影响

Influence of Material Absorption on the Forbidden Band and Defect Mode of the Doped 1D Phononic Crystal

在考虑材料吸收的基础上,利用转移矩阵法计算一维掺杂声子晶体的透射率,研究材料的衰减系数对声子晶体禁带和缺陷模的影响。结果表明:材料的吸收不影响禁带的中心位置和宽度,也不影响缺陷模的中心位置;由于材料的吸收,禁带两侧边缘的透射率减小(均小于1);禁带两侧边缘的透射率和缺陷模的透射率随材料衰减系数的增加而减小,而缺陷模的半高宽随衰减系数的增加而增大;介质的吸收比杂质的吸收对禁带的影响显著,杂质的吸收比介质的吸收对缺陷模的影响显著。

The transfer matrix was employed to study the influence of material absorption on the forbidden band and defect mode of the doped 1D phononic crystal.It is found that material absorption had no effect on the position and width of the forbidden band and the center location of the defect mode.Because of material absorption,the transmission rates of two sides of the forbidden band decreases,and they are less than one.The transmission rates of two sides of the forbidden band and the peak height of defect mode both decreases with the increasing of attenuation coefficient.However,the maximum half full width（MHFW） of the defect mode increases with the increasing of attenuation coefficient.The influence of medium absorption on the forbidden band is more obvious than that of impurity absorption.On the contrary,the impurity absorption affects defect mode more significantly than medium absorption.