搜索

x
中国物理学会期刊

基于弹性拓扑绝缘体的多频段谷锁定拓扑输运研究

CSTR: 32037.14.aps.74.20241322

Multiband valley-locked topological transport based on elastic topological insulator

CSTR: 32037.14.aps.74.20241322
PDF
HTML
导出引用
  • 自拓扑绝缘体概念从量子波领域拓展到经典波领域以来, 谷霍尔拓扑绝缘体因其新奇的物理特性、丰富的波调控方式等优势, 引起了大量的关注, 相关研究得到了快速发展. 本文针对传统谷拓扑绝缘体中边缘态输运容量小、结构不灵活等缺陷, 基于谷锁定原理设计了一种拓扑波导结构. 该结构的原始构形具有矩形脉连接的蜂窝晶格, 利用等效结构参数方法计算了模型的能带结构、输运特性, 发现其布里渊区角点K处有3个狄拉克点. 通过改变结构参数打破体系的空间反演对称性, 实现了3个频段的弹性波模式的拓扑相变; 在两个拓扑绝缘体中间插入具有狄拉克点的声子晶体组成拓扑异质结构, 展示了该结构的拓扑波导态具有多频段、宽度可调、强鲁棒性等优点. 基于该结构设计了能量分束器、能量汇聚器, 实现了对弹性波的多种灵活操控. 此研究不仅丰富了拓扑声学, 所设计的拓扑异质结构在多频段通信与信息处理方面具有潜在的应用前景.

     

    Since the topological insulator concept was expanded from the field of quantum waves to the field of elastic waves, the research related to the elastic system valley Hall insulator has been developed rapidly because of its novel physical properties, rich design ability for wave modulation and simple implementation conditions. To address the limitations of small energy and inflexible structure of the edge-state transmission of valley Hall insulators in traditional structure, a topological waveguide heterostructure is designed based on the valley locking principle. The original configuration of this structure features a honeycomb lattice connected by rectangular veins. The energy band structure and transmission characteristics of the model are calculated using the equivalent structural parameter method. It is found that there are three Dirac points at the corner point K of the Brillouin zone, and the spatial inversion symmetry of the system can be broken by changing the structural parameters, so as to realize the topological phase transition of the out-of-plane body elastic mode in three frequency bands. The topological heterogeneous structure is formed by superimposing Dirac point phonon crystals between two topological insulators, and the topological waveguide state possesses advantages, such as multiband, tunability, and robustness. The structure can be used to design energy splitters and energy convergers to achieve flexible manipulation of elastic waves. This study enriches topological acoustics, and the designed multi-band elastic topological insulator has potential applications in multi-band communication and information processing.

     

    目录

    /

    返回文章
    返回