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journal article·2026-01Open access

Electrical Step‐Edge Contact to a Topological Superconductor Candidate 2M‐WS 2

Qikang Gan, Junwei Song, Hailing Guo, Yuqiang Fang, Xinyan Li, Han Gao, Yiwei Li, Dongdong An, Yujian Zhu, Yangchen He, Kenji Watanabe, Takashi Taniguchi, Yuzheng Guo, Qinghua Zhang, Lin Gu, Daniel A. Rhodes, Zhongkai Liu, Lede Xian, Fuqiang Huang, Lei Wang

Advanced Science· Volume 13· Issue 2
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Abstract

Abstract A topological superconductor (TSC), characterized by a topologically nontrivial bulk state and protected gapless boundary states, is a promising platform for hosting Majorana bound states. However, many TSCs are environmentally sensitive, especially when thinned to 2D atomic layers. This instability poses a major challenge for integrating TSCs into electronic devices. Addressing it requires full encapsulation and high‐quality electrical contact to the TSC layer, which have not yet been achieved. Here, a novel contact geometry is demonstrated for an encapsulated topological superconductor candidate, 2M‐WS 2 , where metal electrodes contact the exposed step‐like edges with a width of only a few nanometers. This structure yields exceptionally low contact resistance ( R C ), down to ∼ 670 Ω·µm for a single unit and ∼ 65 Ω·µm for a six‐unit 2M‐WS 2 device. Below the superconducting critical temperature ( T C ), the TSC–metal interface becomes highly transparent, as evidenced by the Andreev reflection. Furthermore, the step‐edge contact prevents contamination during fabrication, enabling unprecedentedly high‐quality devices. In encapsulated 2M‐WS 2 , twofold rotational symmetry of the critical current ( I C ) and multiple anomalous peaks are observed in the differential resistance ( dV / dI ). The anisotropic I C originates from Fermi velocity variations along in‐plane lattice directions, while the anomalous peaks suggest multigap superconductivity in 2M‐WS 2 . These results reveal the intrinsic properties of 2M‐WS 2 and offer a new path toward high‐performance TSC‐based electronics.
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Research context

Nanomaterials

OpenAlex topics: Topological Materials and Phenomena · 2D Materials and Applications · Graphene research and applications

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

National Laboratory of Solid‐State Microstructures Collaborative Innovation Center of Advanced Microstructures School of Physics Nanjing University Nanjing 210093 China

School of Electrical Engineering and Automation Wuhan University Wuhan 430072 China

Tsientang Institute for Advanced Study Hangzhou 310024 China

School of Materials Science and Engineering Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China

Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

School of Physical Science and Technology ShanghaiTech University Shanghai China

Institute for Advanced Studies Wuhan University Wuhan Hubei 430072 China

Department of Materials Science and Engineering University of Wisconsin Madison WI 53706 USA

Research Center for Electronic and Optical Materials National Institute for Materials Science 1‐1 Namiki Tsukuba 305‐0044 Japan

Research Center for Materials Nanoarchitectonics National Institute for Materials Science 1‐1 Namiki Tsukuba 305‐0044 Japan

Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 149 22761 Hamburg Germany

State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201899/200050 China

Jiangsu Physical Science Research Center Nanjing 210093 China

Funding

National Key Research and Development Program of China · Natural Science Foundation of Jiangsu Province · Basic and Applied Basic Research Foundation of Guangdong Province · Shanghai Rising-Star Program · Science and Technology Commission of Shanghai Municipality

References (38)

Show source-provided references
1. 10.1103/PhysRevLett.104.05700110.1103/PhysRevLett.104.057001 ↗
2. 10.1103/PhysRevLett.107.21700110.1103/PhysRevLett.107.217001 ↗
3. 10.1103/PhysRevLett.112.21700110.1103/PhysRevLett.112.217001 ↗
4. 10.1103/PhysRevLett.114.01700110.1103/PhysRevLett.114.017001 ↗
5. 10.1103/PhysRevB.95.01450210.1103/PhysRevB.95.014502 ↗
6. 10.1038/nphys176210.1038/nphys1762 ↗
7. 10.1103/PhysRevB.79.02452010.1103/PhysRevB.79.024520 ↗
8. 10.1103/PhysRevLett.109.21700410.1103/PhysRevLett.109.217004 ↗
9. Oostinga J. B. · Phys. Rev. X · 2013 · 3
10. 10.1038/nphys303610.1038/nphys3036 ↗
11. 10.1038/ncomms1030310.1038/ncomms10303 ↗
12. 10.1002/adma.20190194210.1002/adma.201901942 ↗
13. 10.1038/s41567-019-0576-710.1038/s41567-019-0576-7 ↗
14. 10.1038/s41467-021-23076-110.1038/s41467-021-23076-1 ↗
15. 10.1021/acs.nanolett.2c0237210.1021/acs.nanolett.2c02372 ↗
16. 10.1038/s41567-022-01812-810.1038/s41567-022-01812-8 ↗
17. 10.1002/aelm.20190046210.1002/aelm.201900462 ↗
18. 10.1103/PhysRevB.105.L16140210.1103/PhysRevB.105.L161402 ↗
19. 10.1021/acsomega.0c0532710.1021/acsomega.0c05327 ↗
20. 10.1126/science.124435810.1126/science.1244358 ↗
21. 10.1038/nnano.2015.7010.1038/nnano.2015.70 ↗
22. 10.1021/acsnano.9b0596510.1021/acsnano.9b05965 ↗
23. 10.1021/acs.nanolett.9b0135510.1021/acs.nanolett.9b01355 ↗
24. 10.1021/acs.nanolett.0c0435710.1021/acs.nanolett.0c04357 ↗
25. 10.1016/j.cpc.2017.09.03310.1016/j.cpc.2017.09.033 ↗
26. 10.1103/PhysRevB.25.451510.1103/PhysRevB.25.4515 ↗
27. 10.1126/science.282.5386.8510.1126/science.282.5386.85 ↗
28. 10.1103/PhysRevB.63.10451010.1103/PhysRevB.63.104510 ↗
29. 10.1103/PhysRevLett.86.558510.1103/PhysRevLett.86.5585 ↗
30. 10.1021/acs.nanolett.8b0392410.1021/acs.nanolett.8b03924 ↗
31. 10.1103/PhysRevLett.72.191010.1103/PhysRevLett.72.1910 ↗
32. Ghorbani S. R. · Appl. Phys. Lett. · 2012 · 100 · 21
33. Xiang F. · Appl. Phys. Lett. · 2013 · 102 · 15
34. 10.1038/s41467-018-02899-510.1038/s41467-018-02899-5 ↗
35. 10.1038/nature0161910.1038/nature01619 ↗
36. 10.1103/PhysRevB.89.02450910.1103/PhysRevB.89.024509 ↗
37. 10.1103/PhysRevB.86.08512110.1103/PhysRevB.86.085121 ↗
38. 10.1038/nphys357910.1038/nphys3579 ↗