Spectroscopic evidence for the realization of a genuine topological nodal-line semimetal in LaSbTe

作     者：Yang Wang Yuting Qian Meng Yang Hongxiang Chen Cong Li Zhiyun Tan Yongqing Cai Wenjuan Zhao Shunye Gao Ya Feng Shiv Kumar Eike F. Schwier Lin Zhao Hongming Weng Youguo Shi Gang Wang Youting Song Yaobo Huang Kenya Shimada Zuyan Xu X. J. Zhou Guodong Liu 

作者机构：Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering Fujian University of Technology Fuzhou 350118 China School of Physics and Electronic Science Zunyi Normal College Zunyi 563006 China Beijing Academy of Quantum Information Sciences Beijing 100193 China Hiroshima Synchrotron Radiation Center Hiroshima University Higashi-Hiroshima Hiroshima 739-0046 Japan Experimentelle Physik VII Universität Würzburg Am Hubland D-97074 Würzburg Germany European Union Songshan Lake Materials Laboratory Dongguan 523808 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Science Beijing 100190 China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204 China Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China 

出 版 物：《Physical Review B》 (Phys. Rev. B)

年 卷 期：2021年第103卷第12期

页      面：125131-125131页

核心收录：

基　　金：National Natural Science Foundation of China, NSFC, (11974404, 51832010, U2032204) National Natural Science Foundation of China, NSFC Chinese Academy of Sciences, CAS, (QYZDB-SSW-SLH043, XDB33000000) Chinese Academy of Sciences, CAS Youth Innovation Promotion Association of the Chinese Academy of Sciences, (11674369, 11865019, 11925408, 17BU025, 18AU001, 2017013) Youth Innovation Promotion Association of the Chinese Academy of Sciences Natural Science Foundation of Beijing Municipality, (Z180008) Natural Science Foundation of Beijing Municipality Beijing Municipal Science and Technology Commission, BMSTC, (2016YFA0300600, 2018YFA0305700, Z191100007219013) Beijing Municipal Science and Technology Commission, BMSTC National Key Research and Development Program of China, NKRDPC, (2016YFA0300602, 2018YFA0305602, 2018YFE0202600) National Key Research and Development Program of China, NKRDPC K. C. Wong Education Foundation, (GJTD-2018-01) K. C. Wong Education Foundation 

主　　题：First-principles calculations Symmetry protected topological states Node-line semimetals Angle-resolved photoemission spectroscopy 

摘      要：The nodal line semimetals have attracted much attention due to their unique topological electronic structure and exotic physical properties. A genuine nodal-line semimetal is qualified by the presence of Dirac nodes along a line in the momentum space that are protected against the spin-orbit coupling. In addition, it requires that the Dirac points lie close to the Fermi level, allowing one to dictate the macroscopic physical properties. Although the material realization of nodal-line semimetals have been theoretically predicted in numerous compounds, only a few of them have been experimentally verified and the realization of a genuine nodal-line semimetal is particularly rare. Here we report the realization of a genuine nodal-line semimetal in LaSbTe. We investigated the electronic structure of LaSbTe by band structure calculations and angle-resolved photoemission (ARPES) measurements. Taking spin-orbit coupling into account, our band structure calculations predict that a nodal line is formed in the boundary surface of the Brillouin zone, which is robust and lies close to the Fermi level. The Dirac nodes along the X-R line in momentum space are directly observed in our ARPES measurements, and the energies of these Dirac nodes are all close to the Fermi level. These results constitute clear evidence that LaSbTe is a genuine nodal-line semimetal, providing a platform to explore for novel phenomena and possible applications associated with the nodal-line semimetals.