Abstract

It was recently reported that circular dichroism in angle-resolved photoemission spectroscopy (CD-ARPES) can be used to observe the Berry curvature in 2H-WSe2 (Cho et al. in Phys Rev Lett 121:186401, 2018). In that study, the mirror plane of the experiment was intentionally set to be perpendicular to the crystal mirror plane, such that the Berry curvature becomes a symmetric function about the experimental mirror plane. In the present study, we performed CD-ARPES on 2H-WSe2 with the crystal mirror plane taken as the experimental mirror plane. Within such an experimental constraint, two experimental geometries are possible for CD-ARPES. The Berry curvature distributions for the two geometries are expected to be antisymmetric about the experimental mirror plane and exactly opposite to each other. Our experimental CD intensities taken with the two geometries were found to be almost opposite near the corners of the 2D projected hexagonal Brillouin zone (BZ) and were almost identical near the center of the BZ. This observation is well explained by taking the Berry curvature or the atomic orbital angular momentum (OAM) into account. The Berry curvature (or OAM) contribution to the CD intensities can be successfully extracted through a comparison of the CD-ARPES data for the two experimental geometries. Thus, the CD-ARPES experimental procedure described provides a method for mapping Berry curvature in the momentum space of topological materials, such as Weyl semimetals.

Details

Title
Studying local Berry curvature in 2H-WSe2 by circular dichroism photoemission utilizing crystal mirror plane
Author
Cho Soohyun 1 ; Jin-Hong, Park 2 ; Huh Soonsang 3 ; Hong Jisook 4 ; Kyung Wonshik 5 ; Park Byeong-Gyu 6 ; Denlinger, J D 7 ; Shim, Ji Hoon 8 ; Kim Changyoung 3 ; Park, Seung Ryong 9 

 Chinese Academy of Sciences, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Shanghai, People’s Republic of China (GRID:grid.9227.e) (ISNI:0000000119573309); Institute for Basic Science (IBS), Center for Correlated Electron Systems, Seoul, Republic of Korea (GRID:grid.410720.0) (ISNI:0000 0004 1784 4496); CAS Center for Excellence in Superconducting Electronics (CENSE), Shanghai, People’s Republic of China (GRID:grid.458459.1) (ISNI:0000 0004 1792 5798) 
 Sungkyunkwan University, Department of Physics, Suwon, Republic of Korea (GRID:grid.264381.a) (ISNI:0000 0001 2181 989X) 
 Institute for Basic Science (IBS), Center for Correlated Electron Systems, Seoul, Republic of Korea (GRID:grid.410720.0) (ISNI:0000 0004 1784 4496); Seoul National University (SNU), Department of Physics and Astronomy, Seoul, Republic of Korea (GRID:grid.31501.36) (ISNI:0000 0004 0470 5905) 
 Lawrence Berkeley National Laboratory, The Molecular Foundry, Berkeley, USA (GRID:grid.184769.5) (ISNI:0000 0001 2231 4551) 
 Institute for Basic Science (IBS), Center for Correlated Electron Systems, Seoul, Republic of Korea (GRID:grid.410720.0) (ISNI:0000 0004 1784 4496) 
 Pohang University of Science and Technology, Pohang Accelerator Laboratory, Pohang, Republic of Korea (GRID:grid.49100.3c) (ISNI:0000 0001 0742 4007) 
 Lawrence Berkeley National Laboratory, Advanced Light Source, Berkeley, USA (GRID:grid.184769.5) (ISNI:0000 0001 2231 4551) 
 Pohang University of Science and Technology, Department of Chemistry, Pohang, Republic of Korea (GRID:grid.49100.3c) (ISNI:0000 0001 0742 4007); Pohang University of Science and Technology, Department of Physics and Division of Advanced Nuclear Engineering, Pohang, Republic of Korea (GRID:grid.49100.3c) (ISNI:0000 0001 0742 4007) 
 Incheon National University, Department of Physics, Incheon, Republic of Korea (GRID:grid.412977.e) (ISNI:0000 0004 0532 7395) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2478660986
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.