无序对二维声子晶体平板负折射成像的影响  

Disorder effect on the focus image of phononic crystal panel with negative refraction

作　　者：李晓春[1,2] 高俊丽[1] 刘绍娥[1] 周科朝[2] 黄伯云[2] 

机构地区：[1]中南大学物理科学与技术学院,长沙410083 [2]中南大学粉末冶金研究院,长沙410083

出　　处：《物理学报》2010年第1期376-380,共5页Acta Physica Sinica

基　　金：中南大学博士后科学基金资助的课题~~

摘　　要：利用多重散射理论分析了位置无序对钢/水声子晶体负折射成像的影响.发现声子晶体负折射成像与周期结构中的方向性通路有关;该方向性通路不同于一般意义上的位置波导,它是声子晶体周期散射的结果;通路中的障碍对成像有较大影响;随着散射体位置无序程度的增加,周期性散射减弱,方向性通路被破坏,成像也随之减弱,甚至消失.By multiple-scattering theory （MST）, disorder effect on the focus image in steel/water phononic crystal panel with negative refraction was investigated. It was found that sonic waves within certain frequency range can propagate along certain directions in periodic crystal and form a focus image with negative refraction characteristics. These directional pathways depend on the periodic scattering in the crystal and are different from the ordinary positional guide. Obstacles in pathways have a deep influence on the focus image. With the increasing of degrec of positional disorder of cylinders, the periodic scattering decreases, pathways are broken, and the focus image becomes blurred or disappears.

关 键 词：声子晶体 负折射 无序 多重散射 

分 类 号：O481[理学—固体物理]