Spin-valley density wave in moiré materials
We introduce and study a minimum two-orbital Hubbard model on a triangular lattice, which captures the key features of both the trilayer ABC-stacked graphene-boron nitride heterostructure and twisted transition metal dichalcogenides in a broad parameter range. Our model comprises first- and second-n...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
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American Physical Society
2021
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| Online Access: | https://hdl.handle.net/1721.1/136945 |
| _version_ | 1826201203930824704 |
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| author | Schrade, Constantin Fu, Liang |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Schrade, Constantin Fu, Liang |
| author_sort | Schrade, Constantin |
| collection | MIT |
| description | We introduce and study a minimum two-orbital Hubbard model on a triangular lattice, which captures the key features of both the trilayer ABC-stacked graphene-boron nitride heterostructure and twisted transition metal dichalcogenides in a broad parameter range. Our model comprises first- and second-nearest neighbor hoppings with valley-contrasting flux that accounts for trigonal warping in the band structure. For the strong-coupling regime with one electron per site, we derive a spin-orbital exchange Hamiltonian and find the semiclassical ground state to be a spin-valley density wave. We show that a relatively small second-neighbor exchange interaction is sufficient to stabilize the ordered state against quantum fluctuations. Effects of spin- and valley Zeeman fields as well as thermal fluctuations are also examined. |
| first_indexed | 2024-09-23T11:48:09Z |
| format | Article |
| id | mit-1721.1/136945 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T11:48:09Z |
| publishDate | 2021 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/1369452023-02-17T20:06:40Z Spin-valley density wave in moiré materials Schrade, Constantin Fu, Liang Massachusetts Institute of Technology. Department of Physics We introduce and study a minimum two-orbital Hubbard model on a triangular lattice, which captures the key features of both the trilayer ABC-stacked graphene-boron nitride heterostructure and twisted transition metal dichalcogenides in a broad parameter range. Our model comprises first- and second-nearest neighbor hoppings with valley-contrasting flux that accounts for trigonal warping in the band structure. For the strong-coupling regime with one electron per site, we derive a spin-orbital exchange Hamiltonian and find the semiclassical ground state to be a spin-valley density wave. We show that a relatively small second-neighbor exchange interaction is sufficient to stabilize the ordered state against quantum fluctuations. Effects of spin- and valley Zeeman fields as well as thermal fluctuations are also examined. 2021-11-01T14:37:58Z 2021-11-01T14:37:58Z 2019-07-10 2019-08-26T21:24:39Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/136945 Phys. Rev. B 100, 035413 (2019) PUBLISHER_POLICY PUBLISHER_POLICY en http://dx.doi.org/10.1103/PhysRevB.100.035413 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. American Physical Society application/pdf American Physical Society American Physical Society |
| spellingShingle | Schrade, Constantin Fu, Liang Spin-valley density wave in moiré materials |
| title | Spin-valley density wave in moiré materials |
| title_full | Spin-valley density wave in moiré materials |
| title_fullStr | Spin-valley density wave in moiré materials |
| title_full_unstemmed | Spin-valley density wave in moiré materials |
| title_short | Spin-valley density wave in moiré materials |
| title_sort | spin valley density wave in moire materials |
| url | https://hdl.handle.net/1721.1/136945 |
| work_keys_str_mv | AT schradeconstantin spinvalleydensitywaveinmoirematerials AT fuliang spinvalleydensitywaveinmoirematerials |