论文标题
带有射影PT对称性的声学晶体中的综合拓扑阶段
Spinful topological phases in acoustic crystals with projective PT symmetry
论文作者
论文摘要
对于物质拓扑阶段的分类，一个重要的考虑因素是系统是无旋转还是跨性别的，因为这两个类具有不同的对称代数，从而产生了根本不同的拓扑阶段。但是，直到最近，从理论上讲，在存在规格对称性的情况下，可以在仪表对称性的情况下进行投影代表对称的代数结构，这可能可以使无旋转和跨性拓扑阶段之间的切换。在这里，我们通过在“无旋转”的声学晶体中实现刺激的时空反演对称性中的跨性拓扑阶段来报告该思想的第一个实验演示。特别是，我们意识到DIII级的一维拓扑相位的相位，其特征是2Z绕组数，其特征是Kramers退化带和Kramers对的拓扑边界模式。因此，我们的工作克服了旋转类对拓扑阶段的基本限制。
For the classification of topological phases of matter, an important consideration is whether a system is spinless or spinful, as these two classes have distinct symmetry algebra that gives rise to fundamentally different topological phases. However, only recently has it been realized theoretically that in the presence of gauge symmetry, the algebraic structure of symmetries can be projectively represented, which possibly enables the switch between spinless and spinful topological phases. Here, we report the first experimental demonstration of this idea by realizing spinful topological phases in "spinless" acoustic crystals with projective space-time inversion symmetry. In particular, we realize a DIII-class one-dimensional topologically gapped phase characterized by a 2Z winding number, which features Kramers degenerate bands and Kramers pair of topological boundary modes. Our work thus overcomes a fundamental constraint on topological phases by spin classes.
