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Title: Quantum spin Hall state in monolayer 1T '-WTe 2

Abstract

A quantum spin Hall (QSH) insulator is a novel two-dimensional quantum state of matter that features quantized Hall conductance in the absence of a magnetic field, resulting from topologically protected dissipationless edge states that bridge the energy gap opened by band inversion and strong spin–orbit coupling. By investigating the electronic structure of epitaxially grown monolayer 1T '-WTe 2 using angle-resolved photoemission (ARPES) and first-principles calculations, we observe clear signatures of topological band inversion and bandgap opening, which are the hallmarks of a QSH state. Scanning tunnelling microscopy measurements further confirm the correct crystal structure and the existence of a bulk bandgap, and provide evidence for a modified electronic structure near the edge that is consistent with the expectations for a QSH insulator. Our results establish monolayer 1T '-WTe 2 as a new class of QSH insulator with large band gap in a robust two-dimensional materials family of transition metal dichalcogenides (TMDCs).

Authors:
 [1];  [2];  [3];  [3];  [3];  [2];  [4];  [4];  [5];  [3];  [6];  [2];  [7]; ORCiD logo [7];  [2];  [8];  [9];  [10];  [11];  [12] more »;  [13];  [13];  [2];  [14]; ORCiD logo [10];  [2] « less
  1. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States). Geballe Lab. for Advanced Materials; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Chinese Academy of Sciences (CAS), Shanghai (China). State Key Lab. of Functional Materials for Informatics, Shanghai Inst. of Microsystem and Information Technology; Shanghai Tech Univ., Shanghai (China). School of Physical Science and Technology
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); Stanford Univ., CA (United States). Geballe Lab. for Advanced Materials
  3. Univ. of California, Berkeley, CA (United States). Dept.of Physics
  4. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)
  5. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Pohang Univ. of Science and Technology (POSTECH) (Korea, Republic of). Max Plank POSTECH Center for Complex Phase Materials; Pusan National Univ., Busan (Korea, Republic of). Dept. of Physics
  6. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Shanghai Tech Univ., Shanghai (China). School of Physical Science and Technology; Pohang Univ. of Science and Technology (POSTECH) (Korea, Republic of). Pohang Accelerator Lab.
  7. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)
  8. Pohang Univ. of Science and Technology (POSTECH) (Korea, Republic of). Pohang Accelerator Lab.
  9. Pusan National Univ., Busan (Korea, Republic of). Dept. of Physics
  10. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
  11. Univ. of Oxford (United Kingdom). Dept. of Physics and Clarendon Lab.
  12. Ikerbasque, Basque Foundation for Science, Bilbao (Spain); CIC nanoGUNE Research Centre, San Sebastian (Spain)
  13. Chinese Academy of Sciences (CAS), Shanghai (China). State Key Lab. of Functional Materials for Informatics, Shanghai Inst. of Microsystem and Information Technology; Shanghai Tech Univ., Shanghai (China). School of Physical Science and Technology
  14. Univ. of California, Berkeley, CA (United States). Dept.of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division; Univ. of California, Berkeley, CA (United States). Kavli Energy Nano Sciences Inst.
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF); National Natural Science Foundation of China (NNSFC)
OSTI Identifier:
1373205
Grant/Contract Number:
AC02-76SF00515; AC02-05CH11231; FA9550-14-1-0277; MAT2014-60996-R
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Physics
Additional Journal Information:
Journal Volume: 13; Journal Issue: 7; Journal ID: ISSN 1745-2473
Publisher:
Nature Publishing Group (NPG)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Tang, Shujie, Zhang, Chaofan, Wong, Dillon, Pedramrazi, Zahra, Tsai, Hsin-Zon, Jia, Chunjing, Moritz, Brian, Claassen, Martin, Ryu, Hyejin, Kahn, Salman, Jiang, Juan, Yan, Hao, Hashimoto, Makoto, Lu, Donghui, Moore, Robert G., Hwang, Chan-Cuk, Hwang, Choongyu, Hussain, Zahid, Chen, Yulin, Ugeda, Miguel M., Liu, Zhi, Xie, Xiaoming, Devereaux, Thomas P., Crommie, Michael F., Mo, Sung-Kwan, and Shen, Zhi-Xun. Quantum spin Hall state in monolayer 1T'-WTe2. United States: N. p., 2017. Web. doi:10.1038/NPHYS4174.
Tang, Shujie, Zhang, Chaofan, Wong, Dillon, Pedramrazi, Zahra, Tsai, Hsin-Zon, Jia, Chunjing, Moritz, Brian, Claassen, Martin, Ryu, Hyejin, Kahn, Salman, Jiang, Juan, Yan, Hao, Hashimoto, Makoto, Lu, Donghui, Moore, Robert G., Hwang, Chan-Cuk, Hwang, Choongyu, Hussain, Zahid, Chen, Yulin, Ugeda, Miguel M., Liu, Zhi, Xie, Xiaoming, Devereaux, Thomas P., Crommie, Michael F., Mo, Sung-Kwan, & Shen, Zhi-Xun. Quantum spin Hall state in monolayer 1T'-WTe2. United States. doi:10.1038/NPHYS4174.
Tang, Shujie, Zhang, Chaofan, Wong, Dillon, Pedramrazi, Zahra, Tsai, Hsin-Zon, Jia, Chunjing, Moritz, Brian, Claassen, Martin, Ryu, Hyejin, Kahn, Salman, Jiang, Juan, Yan, Hao, Hashimoto, Makoto, Lu, Donghui, Moore, Robert G., Hwang, Chan-Cuk, Hwang, Choongyu, Hussain, Zahid, Chen, Yulin, Ugeda, Miguel M., Liu, Zhi, Xie, Xiaoming, Devereaux, Thomas P., Crommie, Michael F., Mo, Sung-Kwan, and Shen, Zhi-Xun. 2017. "Quantum spin Hall state in monolayer 1T'-WTe2". United States. doi:10.1038/NPHYS4174.
@article{osti_1373205,
title = {Quantum spin Hall state in monolayer 1T'-WTe2},
author = {Tang, Shujie and Zhang, Chaofan and Wong, Dillon and Pedramrazi, Zahra and Tsai, Hsin-Zon and Jia, Chunjing and Moritz, Brian and Claassen, Martin and Ryu, Hyejin and Kahn, Salman and Jiang, Juan and Yan, Hao and Hashimoto, Makoto and Lu, Donghui and Moore, Robert G. and Hwang, Chan-Cuk and Hwang, Choongyu and Hussain, Zahid and Chen, Yulin and Ugeda, Miguel M. and Liu, Zhi and Xie, Xiaoming and Devereaux, Thomas P. and Crommie, Michael F. and Mo, Sung-Kwan and Shen, Zhi-Xun},
abstractNote = {A quantum spin Hall (QSH) insulator is a novel two-dimensional quantum state of matter that features quantized Hall conductance in the absence of a magnetic field, resulting from topologically protected dissipationless edge states that bridge the energy gap opened by band inversion and strong spin–orbit coupling. By investigating the electronic structure of epitaxially grown monolayer 1T'-WTe2 using angle-resolved photoemission (ARPES) and first-principles calculations, we observe clear signatures of topological band inversion and bandgap opening, which are the hallmarks of a QSH state. Scanning tunnelling microscopy measurements further confirm the correct crystal structure and the existence of a bulk bandgap, and provide evidence for a modified electronic structure near the edge that is consistent with the expectations for a QSH insulator. Our results establish monolayer 1T'-WTe2 as a new class of QSH insulator with large band gap in a robust two-dimensional materials family of transition metal dichalcogenides (TMDCs).},
doi = {10.1038/NPHYS4174},
journal = {Nature Physics},
number = 7,
volume = 13,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
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