摘要
基于量子谷霍尔效应,设计了一种具有C_(3v)对称的二维谷声子晶体拓扑绝缘体,通过旋转晶格内部散射体的角度改变晶格的拓扑特性,并利用不同拓扑相的二维谷声子晶体构造超胞结构,进而对高阶拓扑角态进行探究.结果表明,旋转角度时,体系的对称性会从C_(3v)对称降为C_(3)对称;当-30°<θ<0°时,体系对应非平庸相,而当0°<θ<30°,体系则对应平庸相;当内部晶格具有非平庸相、外部晶格具有平庸相时,超胞结构Zigzag边界的角落处有3个连续角态,而当内部晶格具有平庸相、外部晶格具有非平庸相时,超胞结构中不存在角态;引入无序缺陷的前后,角态的本征场分布无明显变化,显示出良好的鲁棒性.
Based on the quantum valley-hall effect,a two-dimensional valley phononic crystal topological insulator with C_(3v) symmetry has been designed.By rotating the angle of the scatterers inside the lattice,the topological properties of the lattice were changed.A supercell structure was constructed using two-dimensional valley phononic crystals with different topological phases,and the high-order topological corner states were investigated.The results show that when the rotation angle is changed,the symmetry of the system will decrease from C_(3v) symmetry to C_(3) symmetry.When-30°<θ<0°,the system corresponds to a non-trivial phase,while when 0°<θ<30°,the system corresponds to a trivial phase.When the internal lattice has a non-trivial phase and the external lattice has a trivial phase,there are three continuous corner states at the corners of the Zigzag boundary of the supercell structure.However,when the internal lattice has a trivial phase and the external lattice has a non-trivial phase,there are no corner states in the supercell structure.Before and after introducing disorder defects,the intrinsic field distribution of the corner states shows no significant change,demonstrating good robustness.
作者
蒋婧
孔鹏
邓科
JIANG Jing;KONG Peng;DENG Ke(School of Physics and Electromechanical Engineering,Jishou University,Jishou 416000,Hunan China)
出处
《吉首大学学报(自然科学版)》
2025年第1期39-44,共6页
Journal of Jishou University(Natural Sciences Edition)
关键词
拓扑绝缘体
声子晶体
量子谷霍尔效应
角态
topological insulator
phononic crystal
quantum valley-hall effect
corner state
