Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice
Inspired by the recent discovery of correlated insulating states in twisted bilayer graphene, we study a two-orbital Hubbard model on the honeycomb lattice with two electrons per unit cell. Based on the real-space density matrix renormalization group simulation, we identify a metal-insulator transit...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
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American Physical Society (APS)
2020
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| Online Access: | https://hdl.handle.net/1721.1/125114 |
| _version_ | 1811075558150242304 |
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| author | Zhu, Zheng Sheng, D. N. Fu, Liang |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Zhu, Zheng Sheng, D. N. Fu, Liang |
| author_sort | Zhu, Zheng |
| collection | MIT |
| description | Inspired by the recent discovery of correlated insulating states in twisted bilayer graphene, we study a two-orbital Hubbard model on the honeycomb lattice with two electrons per unit cell. Based on the real-space density matrix renormalization group simulation, we identify a metal-insulator transition around U_{c}/t=2.5–3. In the vicinity of U_{c}, we find strong spin-orbital density wave fluctuations at commensurate wave vectors, accompanied by weaker incommensurate charge density wave fluctuations. The spin-orbital density wave fluctuations are enhanced with increasing system sizes, suggesting the possible emergence of long-range order in the two-dimensional limit. At larger U, our calculations indicate a possible nonmagnetic Mott insulator phase without spin or orbital polarization. Our findings offer new insight into correlated electron phenomena in twisted bilayer graphene and other multiorbital honeycomb materials. |
| first_indexed | 2024-09-23T10:08:09Z |
| format | Article |
| id | mit-1721.1/125114 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T10:08:09Z |
| publishDate | 2020 |
| publisher | American Physical Society (APS) |
| record_format | dspace |
| spelling | mit-1721.1/1251142022-09-26T15:59:01Z Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice Zhu, Zheng Sheng, D. N. Fu, Liang Massachusetts Institute of Technology. Department of Physics Inspired by the recent discovery of correlated insulating states in twisted bilayer graphene, we study a two-orbital Hubbard model on the honeycomb lattice with two electrons per unit cell. Based on the real-space density matrix renormalization group simulation, we identify a metal-insulator transition around U_{c}/t=2.5–3. In the vicinity of U_{c}, we find strong spin-orbital density wave fluctuations at commensurate wave vectors, accompanied by weaker incommensurate charge density wave fluctuations. The spin-orbital density wave fluctuations are enhanced with increasing system sizes, suggesting the possible emergence of long-range order in the two-dimensional limit. At larger U, our calculations indicate a possible nonmagnetic Mott insulator phase without spin or orbital polarization. Our findings offer new insight into correlated electron phenomena in twisted bilayer graphene and other multiorbital honeycomb materials. 2020-05-07T18:31:11Z 2020-05-07T18:31:11Z 2019-08 2019-01 2019-08-29T20:24:16Z Article http://purl.org/eprint/type/JournalArticle 0031-9007 1079-7114 https://hdl.handle.net/1721.1/125114 Physical Review Letters 123, 8 (August 2019): 087602 © 2019 American Physical Society en http://dx.doi.org/10.1103/physrevlett.123.087602 Physical Review Letters 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 (APS) American Physical Society |
| spellingShingle | Zhu, Zheng Sheng, D. N. Fu, Liang Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice |
| title | Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice |
| title_full | Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice |
| title_fullStr | Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice |
| title_full_unstemmed | Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice |
| title_short | Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice |
| title_sort | spin orbital density wave and a mott insulator in a two orbital hubbard model on a honeycomb lattice |
| url | https://hdl.handle.net/1721.1/125114 |
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