基于非点群对称性拓扑光/声子晶体的研究

随着拓扑电子学的快速发展，电子能带拓扑性质的研究已经被推广到经典波动系统中，如电磁波及声波系统。进一步丰富拓扑经典波动系统的实现手段以及挖掘新型拓扑态是目前该领域的研究热点。本项目拟分别通过构建具有滑移反映对称性及螺旋转动对称性的紧束缚模型，研究非点群对称性在能带调控方面的一般机制，然后设计具有相应对称性的光/声子晶体，根据数值计算结果并结合多种理论分析方法，揭示非点群对称性在实现拓扑光/声子晶体中的具体机制；最后还将进一步探索非点群光/声子晶体中的高阶拓扑态及其物理效应。本项目的实施对于丰富拓扑经典波动系统的实现手段以及探索新型拓扑态，具有重要的理论研究意义。

With the rapid development of topological electronics, the studies of topology properties in electronic system have been spread to the classical wave systems, e.g., electromagnetic waves and acoustic waves. So far, to enrich the realization of classical wave systems with topological properties and to excavate the new topological states are research hotspots in these fields. By constructing the tight binding model with glide symmetry and screw symmetry, respectively, this proposal will study the general mechanism of band engineering with nonsymmorphic symmetry. Then according to the simulation results as well as the theoretical analysis methods, this proposal will construct photonic/sonic crystals with nonsymmorphic symmetry to uncover its specific mechanism in realizing the topological photonic/sonic crystals. Finally, this proposal will further explore the high order topological states and their physical effects in the photonic/sonic crystals with nonsymmorphic symmetry. The implementation of this proposal has important theoretical significance for enriching the realization of topological classical systems, as well as exploring exotic topological states.