Dynamically Characterizing the Structures of Dirac Points via Wave Packets  

作　　者：梁丹丹 沈鑫 李志 Dan-Dan Liang;Xin Shen;Zhi Li(Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education),Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter,School of Physics,South China Normal University,Guangzhou 510006,China;Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials,Guangdong-Hong Kong Joint Laboratory of Quantum Matter,Frontier Research Institute for Physics,South China Normal University,Guangzhou 510006,China;College of Sciences,China Jiliang University,Hangzhou 310018,China)

机构地区：[1]Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education),Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter,School of Physics,South China Normal University,Guangzhou 510006,China [2]Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials,Guangdong-Hong Kong Joint Laboratory of Quantum Matter,Frontier Research Institute for Physics,South China Normal University,Guangzhou 510006,China [3]College of Sciences,China Jiliang University,Hangzhou 310018,China

出　　处：《Chinese Physics Letters》2023年第11期9-13,共5页中国物理快报（英文版）

基　　金：supported by the National Key Research and Development Program of China(Grant No.2022YFA1405300);the National Natural Science Foundation of China(Grant Nos.12074180 and 12104430);the Guangdong Basic and Applied Basic Research Foundation(Grant No.2021A1515012350)。

摘　　要：Topological non-trivial band structures are the core problem in the field of topological materials.We investigate the topological band structure in a system with controllable Dirac points from the perspective of wave packet dynamics.By adding a third-nearest-neighboring coupling to the graphene model,additional pairs of Dirac points emerge.The emergence and annihilation of Dirac points result in hybrid and parabolic points,and we show that these band structures can be revealed by the dynamical behaviors of wave packets.In particular,for the gapped hybrid point,the motion of the wave packet shows a one-dimensional Zitterbewegung motion.Furthermore,we also show that the winding number associated with the Dirac point and parabolic point can be determined via the center of mass and spin texture of wave packets,respectively.The results of this work could motivate new experimental methods to characterize a system’s topological signatures through wave packet dynamics,which may also find applications in systems of other exotic topological materials.

关 键 词：DIRAC TOPOLOGICAL PARABOLIC 

分 类 号：O469[理学—凝聚态物理]