Title: Observation of topological superconductivity in a stoichiometric transition metal dichalcogenide 2M-WS₂

Abstract

Topological superconductors (TSCs) are unconventional superconductors with bulk superconducting gap and in-gap Majorana states on the boundary that may be used as topological qubits for quantum computation. Despite their importance in both fundamental research and applications, natural TSCs are very rare. Here, combining state of the art synchrotron and laser-based angle-resolved photoemission spectroscopy, we investigated a stoichiometric transition metal dichalcogenide (TMD), 2M-WS₂ with a superconducting transition temperature of 8.8 K (the highest among all TMDs in the natural form up to date) and observed distinctive topological surface states (TSSs). Furthermore, in the superconducting state, we found that the TSSs acquired a nodeless superconducting gap with similar magnitude as that of the bulk states. These discoveries not only evidence 2M-WS₂ as an intrinsic TSC without the need of sensitive composition tuning or sophisticated heterostructures fabrication, but also provide an ideal platform for device applications thanks to its van der Waals layered structure.

Authors:

Li, Y. W. ^[1]; Zheng, H. J. ^[2]; Fang, Y. Q. ^[3]; Zhang, D. Q. ^[4]; Chen, Y. J. ^[5]; Chen, C. ^[6]; Liang, A. J. ^[7]; Shi, W. J.  ^[8];

• Search DOE PAGES for author "Shi, W. J."
• Search DOE PAGES for ORCID "0000-0003-4541-9086"

Pei, D. ^[9]; Xu, L. X. ^[10]; Liu, S. ^[10]; Pan, J. ^[11]; Lu, D. H.  ^[12];

• Search DOE PAGES for author "Lu, D. H."
• Search DOE PAGES for ORCID "0000-0002-9708-0443"

Hashimoto, M.  ^[12];

• Search DOE PAGES for author "Hashimoto, M."
• Search DOE PAGES for ORCID "0000-0003-1689-8997"

Barinov, A.  ^[13];

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• Search DOE PAGES for ORCID "0000-0003-4125-3779"

Jung, S. W.  ^[14];

• Search DOE PAGES for author "Jung, S. W."
• Search DOE PAGES for ORCID "0000-0002-0748-1615"

Cacho, C.  ^[14];

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• Search DOE PAGES for ORCID "0000-0002-0058-5817"

Wang, M. X. ^[7]; He, Y. ^[15]; Fu, L. ^[16] more »; Zhang, H. J.  ^[17];

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• Search DOE PAGES for ORCID "0000-0002-9958-1102"

Huang, F. Q.  ^[3];

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• Search DOE PAGES for ORCID "0000-0003-0526-5473"

Yang, L. X. ^[18]; Liu, Z. K.  ^[7];

• Search DOE PAGES for author "Liu, Z. K."
• Search DOE PAGES for ORCID "0000-0003-3373-8039"

Chen, Y. L. ^[19] « less

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+ Show Author Affiliations

1. ShanghaiTech Univ. (China); Univ. of Oxford (United Kingdom). Dept. of Physics; ShanghaiTech Laboratory for Topological Physics (China)
2. ShanghaiTech Univ. (China); ShanghaiTech Laboratory for Topological Physics (China); Chinese Academy of Sciences (CAS), Beijing (China)
3. Chinese Academy of Sciences (CAS), Shanghai (China). Shanghai Inst. of Ceramics, State Key Lab. of High Performance Ceramics and Superfine Microstructure; Peking Univ., Beijing (China). State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering
4. China Jiliang Univ., Hangzhou (China). School of Physics; Nanjing Univ. (China). National Laboratory of Solid State Microstructures, School of Physics; Collaborative Innovation Center of Advanced Microstructures, Nanjing (China)
5. Tsinghua Univ., Beijing (China). State Key Laboratory of Low Dimensional Quantum Physics, Dept. of Physics
6. ShanghaiTech Univ. (China); ShanghaiTech Laboratory for Topological Physics (China); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)
7. ShanghaiTech Univ. (China); ShanghaiTech Laboratory for Topological Physics (China)
8. ShanghaiTech Univ. (China). Center for Transformative Science; ShanghaiTech Univ. (China). Shanghai high repetition rate XFEL and extreme light facility (SHINE)
9. Univ. of Oxford (United Kingdom). Dept. of Physics
10. ShanghaiTech Univ. (China); Chinese Academy of Sciences (CAS), Beijing (China)
11. Chinese Academy of Sciences (CAS), Shanghai (China). Shanghai Inst. of Ceramics, State Key Lab. of High Performance Ceramics and Superfine Microstructure
12. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)
13. Elettra-Sincrotrone Trieste (Italy)
14. Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Diamond Light Source, Ltd.
15. Univ. of California, Berkeley, CA (United States). Dept. of Physics
16. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics
17. Nanjing Univ. (China). National Laboratory of Solid State Microstructures, School of Physics; Collaborative Innovation Center of Advanced Microstructures, Nanjing (China)
18. Tsinghua Univ., Beijing (China). State Key Laboratory of Low Dimensional Quantum Physics, Dept. of Physics; Frontier Science Center for Quantum Information, Beijing (China)
19. ShanghaiTech Univ. (China); Univ. of Oxford (United Kingdom). Dept. of Physics; ShanghaiTech Laboratory for Topological Physics (China); Tsinghua Univ., Beijing (China). State Key Laboratory of Low Dimensional Quantum Physics, Dept. of Physics

Publication Date:

Mon May 17 00:00:00 EDT 2021

Research Org.:

Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1814157

Alternate Identifier(s):

OSTI ID: 1812543

Grant/Contract Number:  

AC02-05CH11231; AC02-76SF00515

Resource Type:

Accepted Manuscript

Journal Name:

Nature Communications

Additional Journal Information:

Journal Volume: 12; Journal Issue: 1; Journal ID: ISSN 2041-1723

Publisher:

Nature Publishing Group

Country of Publication:

United States

Language:

English

Subject:

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY