Electrically controllable valence-conduction band reversals in helical trilayer graphene
Fuente:
arXiv
Salvato in:
| Autori principali: | , , , , , , , , , , , , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2026
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866908907016814592 |
|---|---|
| author | Bocarsly, Matan Roy, Indranil Zhi, Weifeng Xia, Li-Qiao Uri, Aviram Kwan, Yves H. Sharpe, Aaron Uzan, Matan Myasoedov, Yuri Watanabe, Kenji Taniguchi, Takashi Devakul, Trithep Jarillo-Herrero, Pablo Zeldov, Eli |
| author_facet | Bocarsly, Matan Roy, Indranil Zhi, Weifeng Xia, Li-Qiao Uri, Aviram Kwan, Yves H. Sharpe, Aaron Uzan, Matan Myasoedov, Yuri Watanabe, Kenji Taniguchi, Takashi Devakul, Trithep Jarillo-Herrero, Pablo Zeldov, Eli |
| contents | In moiré graphene systems, electronic interactions lift spin and valley degeneracies, leading to symmetry-broken ground states. In helical trilayer graphene (HTG), we uncover a distinct interaction-driven mechanism in which the roles of sublattice-polarized valence and conduction bands are cyclically reversed. Using scanning nano-SQUID magnetometry, we detect a series of sharp magnetic signatures consistent with seesaw-like transitions, where occupied and unoccupied valence and conduction bands interchange repeatedly with doping, accompanied by a novel form of magnetic hysteresis. These transitions occur entirely within metallic regimes and leave only weak fingerprints in transport measurements. Self-consistent Hartree-Fock calculations reveal that interactions reorganize all eight low-energy flat bands, driving abrupt changes in orbital magnetization. Our results establish HTG as the first system where electronic interactions provide doping-controlled access to all three internal degrees of freedom - spin, valley, and sublattice - introducing a new class of correlated phase transitions. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2603_21973 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | Electrically controllable valence-conduction band reversals in helical trilayer graphene Bocarsly, Matan Roy, Indranil Zhi, Weifeng Xia, Li-Qiao Uri, Aviram Kwan, Yves H. Sharpe, Aaron Uzan, Matan Myasoedov, Yuri Watanabe, Kenji Taniguchi, Takashi Devakul, Trithep Jarillo-Herrero, Pablo Zeldov, Eli Mesoscale and Nanoscale Physics Strongly Correlated Electrons In moiré graphene systems, electronic interactions lift spin and valley degeneracies, leading to symmetry-broken ground states. In helical trilayer graphene (HTG), we uncover a distinct interaction-driven mechanism in which the roles of sublattice-polarized valence and conduction bands are cyclically reversed. Using scanning nano-SQUID magnetometry, we detect a series of sharp magnetic signatures consistent with seesaw-like transitions, where occupied and unoccupied valence and conduction bands interchange repeatedly with doping, accompanied by a novel form of magnetic hysteresis. These transitions occur entirely within metallic regimes and leave only weak fingerprints in transport measurements. Self-consistent Hartree-Fock calculations reveal that interactions reorganize all eight low-energy flat bands, driving abrupt changes in orbital magnetization. Our results establish HTG as the first system where electronic interactions provide doping-controlled access to all three internal degrees of freedom - spin, valley, and sublattice - introducing a new class of correlated phase transitions. |
| title | Electrically controllable valence-conduction band reversals in helical trilayer graphene |
| topic | Mesoscale and Nanoscale Physics Strongly Correlated Electrons |
| url | https://arxiv.org/abs/2603.21973 |