Coexistence of typeII Dirac point and weak topological phase in ${\mathrm{Pt}}_{3}\mathrm{Sn}$
Abstract
Intriguing topological phases may appear in both insulating and semimetallic states. Topological insulators exhibit topologically nontrivial band inversion, while topological Dirac/Weyl semimetals show “relativistic” linear band crossings. Here, we report an unusual topological state of Pt _{3}Sn, where the two topological features appear simultaneously. Based on firstprinciples calculations, we show that Pt _{3}Sn is a threedimensional weak topological semimetal with topologically nontrivial band inversion between the valence and conduction bands, where the band structure also possesses typeII Dirac points at the boundary of two electron pockets. The formation of the Dirac points can be understood in terms of the representations of relevant symmetry groups and the compatibility relations. The topological surface states appear in accordance with the nontrivial bulk band topology. As a result, the unique coexistence of the two distinct topological features in Pt _{3}Sn enlarges the material scope in topological physics, and is potentially useful for spintronics.
 Authors:
 Ames Lab. and Iowa State Univ., Ames, IA (United States)
 Publication Date:
 Research Org.:
 Ames Laboratory (AMES), Ames, IA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1409680
 Alternate Identifier(s):
 OSTI ID: 1407440
 Report Number(s):
 ISJ9495
Journal ID: ISSN 24699950; PRBMDO
 Grant/Contract Number:
 AC0207CH11358; AC0205CH11231
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review B
 Additional Journal Information:
 Journal Volume: 96; Journal Issue: 20; Journal ID: ISSN 24699950
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
Citation Formats
Kim, Minsung, Wang, Cai Zhuang, and Ho, Kai Ming. Coexistence of typeII Dirac point and weak topological phase in Pt3Sn. United States: N. p., 2017.
Web. doi:10.1103/PhysRevB.96.205107.
Kim, Minsung, Wang, Cai Zhuang, & Ho, Kai Ming. Coexistence of typeII Dirac point and weak topological phase in Pt3Sn. United States. doi:10.1103/PhysRevB.96.205107.
Kim, Minsung, Wang, Cai Zhuang, and Ho, Kai Ming. 2017.
"Coexistence of typeII Dirac point and weak topological phase in Pt3Sn". United States.
doi:10.1103/PhysRevB.96.205107.
@article{osti_1409680,
title = {Coexistence of typeII Dirac point and weak topological phase in Pt3Sn},
author = {Kim, Minsung and Wang, Cai Zhuang and Ho, Kai Ming},
abstractNote = {Intriguing topological phases may appear in both insulating and semimetallic states. Topological insulators exhibit topologically nontrivial band inversion, while topological Dirac/Weyl semimetals show “relativistic” linear band crossings. Here, we report an unusual topological state of Pt3Sn, where the two topological features appear simultaneously. Based on firstprinciples calculations, we show that Pt3Sn is a threedimensional weak topological semimetal with topologically nontrivial band inversion between the valence and conduction bands, where the band structure also possesses typeII Dirac points at the boundary of two electron pockets. The formation of the Dirac points can be understood in terms of the representations of relevant symmetry groups and the compatibility relations. The topological surface states appear in accordance with the nontrivial bulk band topology. As a result, the unique coexistence of the two distinct topological features in Pt3Sn enlarges the material scope in topological physics, and is potentially useful for spintronics.},
doi = {10.1103/PhysRevB.96.205107},
journal = {Physical Review B},
number = 20,
volume = 96,
place = {United States},
year = 2017,
month =
}

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