Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene
Twisted bilayer graphene (TBLG) is one of the simplest van der Waals heterostructures, yet it yields a complex electronic system with intricate interplay between moiré physics and interlayer hybridization effects. We report on electronic transport measurements of high mobility small angle TBLG devic...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
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American Physical Society
2016
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| Online Access: | http://hdl.handle.net/1721.1/105180 https://orcid.org/0000-0003-3648-7706 https://orcid.org/0000-0001-8217-8213 |
| _version_ | 1826217559530143744 |
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| author | Fang, S. Sanchez-Yamagishi, J. D. Watanabe, K. Taniguchi, T. Kaxiras, E. Cao, Y. Fatemi, Valla Luo, J. Y. Jarillo-Herrero, Pablo |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Fang, S. Sanchez-Yamagishi, J. D. Watanabe, K. Taniguchi, T. Kaxiras, E. Cao, Y. Fatemi, Valla Luo, J. Y. Jarillo-Herrero, Pablo |
| author_sort | Fang, S. |
| collection | MIT |
| description | Twisted bilayer graphene (TBLG) is one of the simplest van der Waals heterostructures, yet it yields a complex electronic system with intricate interplay between moiré physics and interlayer hybridization effects. We report on electronic transport measurements of high mobility small angle TBLG devices showing clear evidence for insulating states at the superlattice band edges, with thermal activation gaps several times larger than theoretically predicted. Moreover, Shubnikov–de Haas oscillations and tight binding calculations reveal that the band structure consists of two intersecting Fermi contours whose crossing points are effectively unhybridized. We attribute this to exponentially suppressed interlayer hopping amplitudes for momentum transfers larger than the moiré wave vector. |
| first_indexed | 2024-09-23T17:05:36Z |
| format | Article |
| id | mit-1721.1/105180 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T17:05:36Z |
| publishDate | 2016 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/1051802022-09-29T23:38:36Z Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene Fang, S. Sanchez-Yamagishi, J. D. Watanabe, K. Taniguchi, T. Kaxiras, E. Cao, Y. Fatemi, Valla Luo, J. Y. Jarillo-Herrero, Pablo Massachusetts Institute of Technology. Department of Physics Cao, Y. Fatemi, Valla Luo, J. Y. Jarillo-Herrero, Pablo Twisted bilayer graphene (TBLG) is one of the simplest van der Waals heterostructures, yet it yields a complex electronic system with intricate interplay between moiré physics and interlayer hybridization effects. We report on electronic transport measurements of high mobility small angle TBLG devices showing clear evidence for insulating states at the superlattice band edges, with thermal activation gaps several times larger than theoretically predicted. Moreover, Shubnikov–de Haas oscillations and tight binding calculations reveal that the band structure consists of two intersecting Fermi contours whose crossing points are effectively unhybridized. We attribute this to exponentially suppressed interlayer hopping amplitudes for momentum transfers larger than the moiré wave vector. National Science Foundation (U.S.) (Grant DMR-1405221) Nature Society (Singapore) Gordon and Betty Moore Foundation (Grant GBMF4541) National Science Foundation (U.S.) (Harvard University. Materials Research Science and Engineering Center. Grant DMR-0819762) National Science Foundation (U.S.) (Harvard University. Center for Integrated Quantum Material. Grant ECS-0335765) National Science Foundation (U.S.) (STC Center for Integrated Quantum Materials. Grant DMR- 1231319) United States. Army Research Office. Multidisciplinary University Research Initiative (Award W911NF-14-0247) 2016-11-03T17:47:06Z 2016-11-03T17:47:06Z 2016-09 2016-06 2016-09-07T22:00:07Z Article http://purl.org/eprint/type/JournalArticle 0031-9007 1079-7114 http://hdl.handle.net/1721.1/105180 Cao, Y. et al. “Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene.” Physical Review Letters 117.11 (2016): n. pag. © 2016 American Physical Society https://orcid.org/0000-0003-3648-7706 https://orcid.org/0000-0001-8217-8213 en http://dx.doi.org/10.1103/PhysRevLett.117.116804 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 American Physical Society |
| spellingShingle | Fang, S. Sanchez-Yamagishi, J. D. Watanabe, K. Taniguchi, T. Kaxiras, E. Cao, Y. Fatemi, Valla Luo, J. Y. Jarillo-Herrero, Pablo Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene |
| title | Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene |
| title_full | Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene |
| title_fullStr | Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene |
| title_full_unstemmed | Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene |
| title_short | Superlattice-Induced Insulating States and Valley-Protected Orbits in Twisted Bilayer Graphene |
| title_sort | superlattice induced insulating states and valley protected orbits in twisted bilayer graphene |
| url | http://hdl.handle.net/1721.1/105180 https://orcid.org/0000-0003-3648-7706 https://orcid.org/0000-0001-8217-8213 |
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