文献类型：期刊文献

英文题名：Tunable Weyl half-semimetals in two-dimensional iron-based materials MFeSe (M = Tl, In, Ga)

作者：Huan, Hao[1,2,3,4];Xue, Yang[1,2,3,5];Zhao, Bao[1,2,3,6];Bao, Hairui[1,2,3,4];Liu, Lei[1,2,3,4];Yang, Zhongqin[1,2,3,4]

机构：[1]Fudan Univ, State Key Lab Surface Phys, Shanghai 200433, Peoples R China;[2]Fudan Univ, Key Lab Computat Phys Sci MOE, Shanghai 200433, Peoples R China;[3]Fudan Univ, Dept Phys, Shanghai 200433, Peoples R China;[4]Shanghai Qi Zhi Inst, Shanghai 200030, Peoples R China;[5]East China Univ Sci & Technol, Sch Sci, Shanghai 200237, Peoples R China;[6]Liaocheng Univ, Sch Phys Sci & Informat Technol, Shandong Key Lab Opt Commun Sci & Technol, Liaocheng 252059, Peoples R China

年份：2022

卷号：106

期号：12

外文期刊名：PHYSICAL REVIEW B

收录：;EI(收录号：20223912804655);WOS:【SCI-EXPANDED(收录号:WOS:000863105300005)】；

基金：ACKNOWLEDGMENTS This work was supported by National Natural Science Foundation of China under Grants No. 11874117, No. 12174059, and No. 11904101 and Natural Science Foundation of Shanghai under Grant No. 21ZR1408200. The calculations were performed at the High-Performance Computational Cen-ter (HPCC) of the Department of Physics at Fudan University.

语种：英文

外文关键词：Density functional theory - Energy gap - Gallium compounds - Iron - Iron compounds - Microelectronics - Selenium compounds - Topology

摘要：The layered iron chalcogenide materials have attracted considerable attention recently for their exotic su-perconductivity at relatively high temperatures. Topological phases are, however, seldom proposed in these materials. Based on density-functional theory calculations together with symmetry analysis, 100% spin-polarized Weyl semimetals, namely Weyl half semimetals (WHSMs), are predicted in two-dimensional (2D) TlFeSe and GaFeSe monolayers, built based on FeSe monolayers. The acquired Weyl fermions are protected by a nonsymmorphic symmetry. Dissimilarly, the InFeSe monolayer is found to be a quantum anomalous Hall (QAH) insulator with a large band gap (403 meV). By tuning the magnetization direction, the monolayers can vary from a WHSM to a QAH insulator or vice versa. The phase-transition mechanism is analyzed by using an effective k & BULL; p model. Our work provides a pathway to carry out the fascinating 2D WHSMs and the QAH effect in one material which will have promising applications in not only spintronics but also topological microelectronics.