磁流变弹性体基拓扑声子晶体弹性波传输可调性研究

Research on elastic wave transmission adjustability of topological phononic crystals based on magnetorheological elastomers

设计了一种由磁流变弹性体、硅胶、钨三种材料组成二维三组元蜂窝状的声子晶体,通过打破二维蜂窝状声子晶体的空间对称性实现了K点的狄拉克锥从打开到闭合后再打开状态,实现了第8和第9能带间的能带反转,通过构造类似量子霍尔效应的赝自旋态实现了弹性波的拓扑传输。通过有限元法和平面波展开法研究了磁场与声子晶体禁带频率范围的变化规律,实现了弹性波拓扑传输通道的智能调节。此外,探明了不同金属芯体材料密度对声子晶体带隙的影响,研究结果可以为新型智能材料的研究及弹性波的精确引导等提供相应的参考。

In this paper,a two-dimensional three-element honeycomb phononic crystal composed of magnetorheological elastomers,silica gel,and tungsten is designed,and the K-point Dirac is realized by breaking the spatial symmetry of the two-dimensional honeycomb phononic crystal.The cone changes from opening to closing and then opening again,realizing the energy band inversion between the 8th and 9th bands,and constructing a pseudo-spin state similar to the quantum Hall effect to realize the topological transmission of elastic waves.Through the finite element method and the plane wave expansion method,the changing laws of the magnetic field and the frequency range of the phononic crystal band gap are studied,and the intelligent adjustment of the acoustic wave topology transmission channel is realized.In addition,the effects of different metal core material densities on the band gap of phononic crystals have been explored.The results can be used as a reference for the study of new metamaterials and the accurate guidance of elastic waves.