Evolution of Weyl nodes in Ni-doped thallium niobate pyrochlore Tl_(2-x)Ni_(x)Nb_(2)O_(7)

作     者：Yuefang Hu Changming Yue Danwen Yuan Jiacheng Gao Zhigao Huang Zhong Fang Chen Fang Hongming Weng Wei Zhang 

作者机构：Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy MaterialsCollege of Physics and EnergyFujian Normal UniversityFuzhou 350117China Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and EngineeringFuzhou 350117China Department of PhysicsUniversity of FribourgFribourg 1700Switzerland Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials LaboratoryDongguan 523808China 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学：物理学、力学、天文学（英文版）)

年 卷 期：2022年第65卷第9期

页      面：104-111页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11974076,11925408,11921004,and 12188101) Key Project of Natural Science Foundation of Fujian Province(Grant No.2021J02012) Ministry of Science and Technology of China(Grant No.2018YFA0305700) Chinese Academy of Sciences(Grant No.XDB33000000) K.C.Wong Education Foundation(Grant No.GJTD-2018-01) Informatization Plan of Chinese Academy of Sciences(Grant No.CAS-WX2021SF-0102) supported by the Swiss National Science Foundation(Grant No.200021-196966) 

主　　题：magnetic Weyl semimetal pyrochlore topological phase transition Chern number anomalous Hall effect 

摘      要：The magnetic Weyl semimetal(WSM)is important for fundamental physics and potential applications due to its spontaneous magnetism,robust band topology,and enhanced Berry *** possesses many unique quantum effects,including a large intrinsic anomalous Hall effect,Fermi arcs,and chiral *** this work,using ab initio calculations,we propose that Nidoped pyrochlore Tl2Nb2O7is a magnetic WSM caused by the exchange field splitting on bands around its quadratic band crossing *** exchange field tuned by Ni 3d on-site Coulomb interaction parameter U drives the evolution of Weyl nodes and the resulting topological phase *** Weyl nodes can exist at generic points in the Brillouin zone and are hard to identify exactly,their creation and annihilation,i.e.,the change in their number,chirality,and distribution,have been consistently confirmed with a combined theoretical approach,which employs parity criterion,symmetry indicator analysis,and the Wilson loop of the Wannier *** find that Weyl nodes remain in a large range of U and are close to the Fermi level,which makes the experimental observation very *** think that this method and our proposal of magnetic WSM will be useful in finding more WSMs and add to the understanding of the topological phase transition.