论文标题
音调晶体中的混合阶拓扑绝缘子
Hybrid-order topological insulators in a phononic crystal
论文作者
论文摘要
拓扑阶段，包括常规的一阶和高阶拓扑绝缘子和半学，在凝结的物理学和材料科学领域中出现了一个繁荣的话题。通常，拓扑绝缘子的特征是固定阶拓扑不变，并且表现出相关的散装对应关系。在这里，我们在双层音响晶体中实现了一种新型的拓扑绝缘子，该晶体晶体同时托管了一阶和二阶拓扑结构，此处称为混合级拓扑绝缘子。一维无间隙的螺旋边缘状态，零维角状态在同一系统中共存。新的杂种拓扑阶段可能会在拓扑声学设备中产生新的应用。
Topological phases, including the conventional first-order and higher-order topological insulators and semimetals, have emerged as a thriving topic in the fields of condensed-matter physics and material science. Usually, a topological insulator is characterized by a fixed order topological invariant and exhibits associated bulk-boundary correspondence. Here, we realize a new type of topological insulator in a bilayer phononic crystal, which hosts simultaneously the first-order and second-order topologies, referred here as the hybrid-order topological insulator. The one-dimensional gapless helical edge states, and zero-dimensional corner states coexist in the same system. The new hybrid-order topological phase may produce novel applications in topological acoustic devices.
