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Updated: Jun 17, 2026
11:24
Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
Published on: July 11, 2025
Quantum anomalous Hall effect in rhombohedral multilayer graphene/h-BN moiré superlattices
Jiannan Hua1,2, Jing Ding1, Wei Zhu1,2
1Department of Physics, School of Science, Westlake University, Hangzhou 310030, People's Republic of China.
Summary
Rhombohedral multilayer graphene aligned with hexagonal boron nitride exhibits quantum anomalous Hall effects. This review explores experimental and theoretical advancements in these correlated topological phases.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Physics
Background:
- Rhombohedral multilayer graphene (RMG) aligned with hexagonal boron nitride ($h$-BN) has emerged as a key platform for studying correlated topological matter.
- Recent observations show robust quantum anomalous Hall (QAH) effects in these systems, particularly at filling factor $\nu=1$.
Purpose of the Study:
- To synthesize experimental and theoretical progress in understanding interaction-driven topological phases in RMG/$h$-BN systems.
- To review the development from initial Chern insulators to quantized QAH states and discuss theoretical frameworks.
- To highlight the role of moiré potential and electron-electron interactions in forming these phases.
Main Methods:
- Experimental synthesis and characterization of RMG/$h$-BN heterostructures.
- Theoretical modeling, including continuum models and many-body approaches.
- Analysis of experimental hallmarks and theoretical predictions for topological phases.
Main Results:
- Experimental realization of Chern insulators and quantized QAH states in various RMG thicknesses.
- Theoretical understanding of the cooperative roles of moiré potential and electron-electron interactions.
- Identification of potential topological phases like the anomalous Hall crystal (AHC).
Conclusions:
- RMG/$h$-BN systems provide a versatile platform for exploring correlated topological quantum matter.
- A reconciled physical picture emerges regarding the interplay of interactions, displacement fields, and moiré potentials.
- Open questions and future research directions are identified for advancing the field.
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