Directional mechanical response in the bulk of topological metamaterials
Directional mechanical response in the bulk of topological metamaterials
复制标题
大量拓扑超材料中的定向机械响应
DOI：
10.1088/1367-2630/aa7155
复制
发表时间：
2016
影响因子：
3.3
通讯作者：
D. Rocklin
中科院分区：
文献类型：
--
作者：
D. Rocklin
机械超材料是那些设计用于以新颖和理想的方式传递力和运动的结构。最近，Kane和Lubensky证明了在临界机械稳定点的晶格（麦克斯韦晶格）具有拓扑不变量，该拓扑不变量描述了松弛的零能量边缘模式的分布。在这里，我们表明，在这些晶格的大部分中的一个点上施加力会产生定向机械响应，其中仅在力的一侧引起应力或应变。这提供了机械极化的体积度量和朝向或远离结构的部分传递应力和应变的设计原理。我们还表征了去除键对材料结构和松弛模式的影响，建立了边缘模式和批量响应之间的关系。
Mechanical metamaterials are those structures designed to convey force and motion in novel and desirable ways. Recently, Kane and Lubensky showed that lattices at the point of marginal mechanical stability (Maxwell lattices) possess a topological invariant that describes the distribution of floppy, zero-energy edge modes. Here, we show that applying force at a point in the bulk of these lattices generates a directional mechanical response, in which stress or strain is induced only on one side of the force. This provides both a bulk metric for mechanical polarization and a design principle to convey stresses and strains towards or away from parts of the structure. We also characterize the effects of removing bonds on the material’s structure and floppy modes, establishing a relationship between edge modes and bulk response.