Geometric origin of spontaneous chiral symmetry breaking in rhombohedral graphene
ORAL
Abstract
Spontaneous chiral symmetry breaking was predicted in charge-neutral rhombohedral graphene systems [1]. The predicted broken symmetry states, such as layer antiferromagnetic states and quantum anomalous Hall states of large Chern numbers, were experimentally observed in a variety of devices of different dielectric environments and different layer thickness [2-7]. We investigate the geometric origin of this weak interaction instability, elucidate its universal robustness, and identify a potential pathway for developing correlated topological phases of matter.
[1] Zhang, F. et al. Spontaneous quantum Hall states in chirally stacked few-layer graphene systems, Phys. Rev. Lett. 106, 156801 (2011).
[2] Velasco, J. et al. Transport spectroscopy of symmetry-broken insulating states in bilayer graphene, Nature Nanotechnol. 7, 156 (2012).
[3] Shi, Y. et al. Electronic phase separation in multilayer rhombohedral graphite, Nature 584, 210–214 (2020).
[4] Geisenhof, F. R. et al. Quantum anomalous Hall octet driven by orbital magnetism in bilayer graphene, Nature 598, 53–58 (2021).
[5] Winterer, F. et al. Ferroelectric and spontaneous quantum Hall states in intrinsic rhombohedral trilayer graphene, Nat. Phys. 20, 422–427 (2024).
[6] Sha, Y. et al. Observation of a Chern insulator in crystalline ABCA-tetralayer graphene with spin-orbit coupling, Science 384, 414-419(2024).
[7] Han, T. et al. Large quantum anomalous Hall effect in spin-orbit proximitized rhombohedral graphene, Science 384, 647-651(2024).
[1] Zhang, F. et al. Spontaneous quantum Hall states in chirally stacked few-layer graphene systems, Phys. Rev. Lett. 106, 156801 (2011).
[2] Velasco, J. et al. Transport spectroscopy of symmetry-broken insulating states in bilayer graphene, Nature Nanotechnol. 7, 156 (2012).
[3] Shi, Y. et al. Electronic phase separation in multilayer rhombohedral graphite, Nature 584, 210–214 (2020).
[4] Geisenhof, F. R. et al. Quantum anomalous Hall octet driven by orbital magnetism in bilayer graphene, Nature 598, 53–58 (2021).
[5] Winterer, F. et al. Ferroelectric and spontaneous quantum Hall states in intrinsic rhombohedral trilayer graphene, Nat. Phys. 20, 422–427 (2024).
[6] Sha, Y. et al. Observation of a Chern insulator in crystalline ABCA-tetralayer graphene with spin-orbit coupling, Science 384, 414-419(2024).
[7] Han, T. et al. Large quantum anomalous Hall effect in spin-orbit proximitized rhombohedral graphene, Science 384, 647-651(2024).
*We acknowledge support from the National Science Foundation under grants DMR-2414726, DMR-1945351, and DMR-2324033, as well as support from the Welch Foundation under grant AT-2264-20250403.
–
Presenters
-
Tianyi Xu
- University of Texas at Dallas