Robustness and universality of surface states in Dirac materials
Ballistically propagating topologically protected states harbor exotic transport phenomena of wide interest. Here we describe a nontopological mechanism that produces such states at the surfaces of generic Dirac materials, giving rise to propagating surface modes with energies near the bulk band cro...
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| Format: | Article |
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National Academy of Sciences (U.S.)
2019
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| Online Access: | http://hdl.handle.net/1721.1/121119 https://orcid.org/0000-0003-4193-6254 https://orcid.org/0000-0002-4268-731X |
| _version_ | 1811078911910477824 |
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| author | Shtanko, Oles Levitov, Leonid |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Shtanko, Oles Levitov, Leonid |
| author_sort | Shtanko, Oles |
| collection | MIT |
| description | Ballistically propagating topologically protected states harbor exotic transport phenomena of wide interest. Here we describe a nontopological mechanism that produces such states at the surfaces of generic Dirac materials, giving rise to propagating surface modes with energies near the bulk band crossing. The robustness of surface states originates from the unique properties of Dirac–Bloch wavefunctions which exhibit strong coupling to generic boundaries. Surface states, described by Jackiw–Rebbi-type bound states, feature a number of interesting properties. Mode dispersion is gate tunable, exhibiting a wide variety of different regimes, including nondispersing flat bands and linear crossings within the bulk bandgap. The ballistic wavelike character of these states resembles the properties of topologically protected states; however, it requires neither topological restrictions nor additional crystal symmetries. The Dirac surface states are weakly sensitive to surface disorder and can dominate edge transport at the energies near the Dirac point. |
| first_indexed | 2024-09-23T11:07:11Z |
| format | Article |
| id | mit-1721.1/121119 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T11:07:11Z |
| publishDate | 2019 |
| publisher | National Academy of Sciences (U.S.) |
| record_format | dspace |
| spelling | mit-1721.1/1211192022-09-27T17:16:52Z Robustness and universality of surface states in Dirac materials Shtanko, Oles Levitov, Leonid Massachusetts Institute of Technology. Department of Physics Shtanko, Oles Levitov, Leonid Ballistically propagating topologically protected states harbor exotic transport phenomena of wide interest. Here we describe a nontopological mechanism that produces such states at the surfaces of generic Dirac materials, giving rise to propagating surface modes with energies near the bulk band crossing. The robustness of surface states originates from the unique properties of Dirac–Bloch wavefunctions which exhibit strong coupling to generic boundaries. Surface states, described by Jackiw–Rebbi-type bound states, feature a number of interesting properties. Mode dispersion is gate tunable, exhibiting a wide variety of different regimes, including nondispersing flat bands and linear crossings within the bulk bandgap. The ballistic wavelike character of these states resembles the properties of topologically protected states; however, it requires neither topological restrictions nor additional crystal symmetries. The Dirac surface states are weakly sensitive to surface disorder and can dominate edge transport at the energies near the Dirac point. United States. National Science Foundation. Center for Integrated Quantum Materials. (Award DMR-1231319) United States. Department of Energy. Office of Basic Energy Sciences (Award de-sc0001088) United States. Army Research Office (Grant W911NF-18-1-0116) 2019-03-29T19:37:43Z 2019-03-29T19:37:43Z 2018-05 2017-12 2019-03-29T16:06:21Z Article http://purl.org/eprint/type/JournalArticle 0027-8424 1091-6490 http://hdl.handle.net/1721.1/121119 Shtanko, Oles and Leonid Levitov. “Robustness and Universality of Surface States in Dirac Materials.” Proceedings of the National Academy of Sciences of the United States of America 115, 23 (May 2018): 5908–5913. doi:10.1073/pnas.1722663115. © 2018 The Author(s) https://orcid.org/0000-0003-4193-6254 https://orcid.org/0000-0002-4268-731X http://dx.doi.org/10.1073/PNAS.1722663115 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 National Academy of Sciences (U.S.) PNAS |
| spellingShingle | Shtanko, Oles Levitov, Leonid Robustness and universality of surface states in Dirac materials |
| title | Robustness and universality of surface states in Dirac materials |
| title_full | Robustness and universality of surface states in Dirac materials |
| title_fullStr | Robustness and universality of surface states in Dirac materials |
| title_full_unstemmed | Robustness and universality of surface states in Dirac materials |
| title_short | Robustness and universality of surface states in Dirac materials |
| title_sort | robustness and universality of surface states in dirac materials |
| url | http://hdl.handle.net/1721.1/121119 https://orcid.org/0000-0003-4193-6254 https://orcid.org/0000-0002-4268-731X |
| work_keys_str_mv | AT shtankooles robustnessanduniversalityofsurfacestatesindiracmaterials AT levitovleonid robustnessanduniversalityofsurfacestatesindiracmaterials |