Quantum anomalous, quantum spin, and quantum valley Hall effects in pentalayer rhombohedral graphene
| Autor: | Kudo, Koji, Nakai, Ryota, Nomura, Kentaro |
|---|---|
| Rok vydání: | 2024 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| Popis: | Recent experiments in pentalayer rhombohedral graphene moir\'e superlattice have observed the quantum anomalous Hall effect at the moir\'e filling factor $\nu=1$ and various fractions. These effects result from a flat Chern band induced by electron-electron interactions. In this Letter, we show that the many-body effects at $\nu=2$ give rise to the quantum spin Hall and quantum valley Hall states, even without spin-orbit couplings or valley-dependent potentials, in addition to the quantum anomalous Hall state. These three topological states can be selectively induced by applying and tilting a magnetic field. Furthermore, we demonstrate that at $\nu=3$ and $4$, a combination of the Wigner-like crystal state and topological states can be the ground state. Consequently, the relation between states at the filling factor $\nu$ and its particle-hole counterpart $4-\nu$ breaks down, which contrasts with the conventional quantum Hall effect in graphene. Comment: 11 pages, 7 figures |
| Databáze: | arXiv |
| Externí odkaz: |
|