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Title: Asymmetric mass acquisition in LaBi. Topological semimetal candidate

Abstract

We use our high resolution He-lamp-based, tunable laser-based angle-resolved photoemission spectroscopy measurements and density functional theory calculations to study the electronic properties of LaBi, a binary system that was proposed to be a member of a new family of topological semimetals. Both bulk and surface bands are present in the spectra. Furthermore, the dispersion of the surface state is highly unusual. It resembles a Dirac cone, but upon closer inspection we can clearly detect an energy gap. The bottom band follows roughly a parabolic dispersion. The dispersion of the top band remains very linear, “V” -shape like, with the tip approaching very closely to the extrapolated location of Dirac point. Finally, such asymmetric mass acquisition is highly unusual and opens a possibility of a new topological phenomenon that has yet to be understood.

Authors:
 [1];  [1];  [2];  [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. Ames Lab., Ames, IA (United States). Division of Materials Science and Engineering; Iowa State Univ., Ames, IA (United States). Dept. of Physics and Astronomy
  2. Ames Lab., Ames, IA (United States). Division of Materials Science and Engineering
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
OSTI Identifier:
1326850
Alternate Identifier(s):
OSTI ID: 1298340
Report Number(s):
IS-J-9084
Journal ID: ISSN 2469-9950; PRBMDO
Grant/Contract Number:
AC02-07CH11358; DMR-1420451
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 94; Journal Issue: 8; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Wu, Yun, Kong, Tai, Wang, Lin-Lin, Johnson, D. D., Mou, Daixiang, Huang, Lunan, Schrunk, Benjamin, Bud'ko, S. L., Canfield, P. C., and Kaminski, Adam. Asymmetric mass acquisition in LaBi. Topological semimetal candidate. United States: N. p., 2016. Web. doi:10.1103/PhysRevB.94.081108.
Wu, Yun, Kong, Tai, Wang, Lin-Lin, Johnson, D. D., Mou, Daixiang, Huang, Lunan, Schrunk, Benjamin, Bud'ko, S. L., Canfield, P. C., & Kaminski, Adam. Asymmetric mass acquisition in LaBi. Topological semimetal candidate. United States. doi:10.1103/PhysRevB.94.081108.
Wu, Yun, Kong, Tai, Wang, Lin-Lin, Johnson, D. D., Mou, Daixiang, Huang, Lunan, Schrunk, Benjamin, Bud'ko, S. L., Canfield, P. C., and Kaminski, Adam. Thu . "Asymmetric mass acquisition in LaBi. Topological semimetal candidate". United States. doi:10.1103/PhysRevB.94.081108. https://www.osti.gov/servlets/purl/1326850.
@article{osti_1326850,
title = {Asymmetric mass acquisition in LaBi. Topological semimetal candidate},
author = {Wu, Yun and Kong, Tai and Wang, Lin-Lin and Johnson, D. D. and Mou, Daixiang and Huang, Lunan and Schrunk, Benjamin and Bud'ko, S. L. and Canfield, P. C. and Kaminski, Adam},
abstractNote = {We use our high resolution He-lamp-based, tunable laser-based angle-resolved photoemission spectroscopy measurements and density functional theory calculations to study the electronic properties of LaBi, a binary system that was proposed to be a member of a new family of topological semimetals. Both bulk and surface bands are present in the spectra. Furthermore, the dispersion of the surface state is highly unusual. It resembles a Dirac cone, but upon closer inspection we can clearly detect an energy gap. The bottom band follows roughly a parabolic dispersion. The dispersion of the top band remains very linear, “V” -shape like, with the tip approaching very closely to the extrapolated location of Dirac point. Finally, such asymmetric mass acquisition is highly unusual and opens a possibility of a new topological phenomenon that has yet to be understood.},
doi = {10.1103/PhysRevB.94.081108},
journal = {Physical Review B},
number = 8,
volume = 94,
place = {United States},
year = {Thu Aug 18 00:00:00 EDT 2016},
month = {Thu Aug 18 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 14works
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