基于固体软板与空心圆柱双负声超常材料实现

Double Negative Acoustic Metamaterials Based on a Soft Slid Plate and Hollow Steel Cylinders

在环氧树脂软板中周期性引入钢柱,利用其表面模集体共振激发,实现了负的有效质量密度响应.在空心钢柱周期性切缝构造亥姆赫兹共振腔结构,实现了负的体模量响应.复合以上2种结构,实现了质量密度和体模量同时为负的双负声超常材料.与现有的基于三维共振单元的双负材料相比,这种基于二维共振单元的双负超常材料结构更简单,易于制备.

A water-immersed epoxy plate injected with periodical steel columns is designed to achieve neg- ative-dynamic-mass response, which arises from the collective excitation of surface modes in the plate. A slit hollow steel cylinder immersed in water is designed as a Helmholtz resonator to achieve negative bulk modulus. By combining these two designed structures together, an acoustic metamaterial simultaneously possessing a negative mass density and bulk modulus is realized. Compared to previous realized three-dimensional double negative metamaterials, this two-dimensional double negative metamaterial is much easy to be fabricated.