Topology on a new facet of bismuth
Bismuth-based materials have been instrumental in the development of topological physics, even though bulk bismuth itself has been long thought to be topologically trivial. A recent study has, however, shown that bismuth is in fact a higher-order topological insulator featuring one-dimensional (1D)...
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| Format: | Article |
| Language: | English |
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Proceedings of the National Academy of Sciences
2020
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| Online Access: | https://hdl.handle.net/1721.1/124469 |
| _version_ | 1811069940215578624 |
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| author | Ma, Qiong Xu, Su-Yang Fu, Liang |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Ma, Qiong Xu, Su-Yang Fu, Liang |
| author_sort | Ma, Qiong |
| collection | MIT |
| description | Bismuth-based materials have been instrumental in the development of topological physics, even though bulk bismuth itself has been long thought to be topologically trivial. A recent study has, however, shown that bismuth is in fact a higher-order topological insulator featuring one-dimensional (1D) topological hinge states protected by threefold rotational and inversion symmetries. In this paper, we uncover another hidden facet of the band topology of bismuth by showing that bismuth is also a first-order topological crystalline insulator protected by a twofold rotational symmetry. As a result, its (110) ¯ surface exhibits a pair of gapless Dirac surface states. Remarkably, these surface Dirac cones are “unpinned” in the sense that they are not restricted to locate at specific k points in the (110) ¯ surface Brillouin zone. These unpinned 2D Dirac surface states could be probed directly via various spectroscopic techniques. Our analysis also reveals the presence of a distinct, previously uncharacterized set of 1D topological hinge states protected by the twofold rotational symmetry. Our study thus provides a comprehensive understanding of the topological band structure of bismuth. |
| first_indexed | 2024-09-23T08:19:18Z |
| format | Article |
| id | mit-1721.1/124469 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T08:19:18Z |
| publishDate | 2020 |
| publisher | Proceedings of the National Academy of Sciences |
| record_format | dspace |
| spelling | mit-1721.1/1244692022-09-30T08:59:53Z Topology on a new facet of bismuth Ma, Qiong Xu, Su-Yang Fu, Liang Massachusetts Institute of Technology. Department of Physics Multidisciplinary Bismuth-based materials have been instrumental in the development of topological physics, even though bulk bismuth itself has been long thought to be topologically trivial. A recent study has, however, shown that bismuth is in fact a higher-order topological insulator featuring one-dimensional (1D) topological hinge states protected by threefold rotational and inversion symmetries. In this paper, we uncover another hidden facet of the band topology of bismuth by showing that bismuth is also a first-order topological crystalline insulator protected by a twofold rotational symmetry. As a result, its (110) ¯ surface exhibits a pair of gapless Dirac surface states. Remarkably, these surface Dirac cones are “unpinned” in the sense that they are not restricted to locate at specific k points in the (110) ¯ surface Brillouin zone. These unpinned 2D Dirac surface states could be probed directly via various spectroscopic techniques. Our analysis also reveals the presence of a distinct, previously uncharacterized set of 1D topological hinge states protected by the twofold rotational symmetry. Our study thus provides a comprehensive understanding of the topological band structure of bismuth. China. Ministry of Science and Technology (Grant MOST107-2627-E-006-001) United States. Department of Energy. Division of Materials Sciences and Engineering (Award DE-SC0018945) United States. Department of Energy. Office of Basic Energy Science (ES Grant DE-FG02-07ER46352) United States. Department of Energy (GrantDE-AC02-05CH11231) National Science Foundation (U.S.) (Grant DMR-1231319) 2020-04-01T12:38:22Z 2020-04-01T12:38:22Z 2019-06-13 2020-02-13T13:27:29Z Article http://purl.org/eprint/type/JournalArticle 0027-8424 1091-6490 https://hdl.handle.net/1721.1/124469 Hsu, Chuang-Han et al. "Topology on a new facet of bismuth." Proceedings of the National Academy of Sciences of the United States of America 116 (2019): 13255-13259 © 2019 The Author(s) en 10.1073/pnas.1900527116 Proceedings of the National Academy of Sciences of the United States of America Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf Proceedings of the National Academy of Sciences PNAS |
| spellingShingle | Multidisciplinary Ma, Qiong Xu, Su-Yang Fu, Liang Topology on a new facet of bismuth |
| title | Topology on a new facet of bismuth |
| title_full | Topology on a new facet of bismuth |
| title_fullStr | Topology on a new facet of bismuth |
| title_full_unstemmed | Topology on a new facet of bismuth |
| title_short | Topology on a new facet of bismuth |
| title_sort | topology on a new facet of bismuth |
| topic | Multidisciplinary |
| url | https://hdl.handle.net/1721.1/124469 |
| work_keys_str_mv | AT maqiong topologyonanewfacetofbismuth AT xusuyang topologyonanewfacetofbismuth AT fuliang topologyonanewfacetofbismuth |