English

Stack of correlated insulating states in bilayer graphene kagome superlattice

Mesoscale and Nanoscale Physics 2026-02-19 v1

Abstract

Graphene-based systems have emerged as a rich platform for exploring emergent quantum phenomena-including superconductivity, magnetism, and correlated insulating behavior-arising from flat electronic bands that enhance many-body interactions. Realizing such flat bands has thus far relied primarily on moir\'e graphene superlattices or rhombohedral stacking graphene systems, both of which face challenges in reproducibility and tunability. Here, we introduce an artificial Kagome superlattice in bilayer graphene, engineered via nanopatterning of the dielectric substrate to create a precisely defined and electrostatically tunable periodic potential. Magnetotransport measurements reveal the emergence of a stack of correlated insulating states at moderate superlattice potentials, characteristic of strong electron-electron interactions within Kagome-induced flat bands. As temperature increases, these correlated gaps collapse, signaling the thermal suppression of interaction-driven states. Continuum-model calculations confirm the formation of multiple flat minibands and reproduce the observed evolution of band reconstruction. Our results establish dielectric-patterned graphene superlattices as a robust and controllable architecture for realizing flat-band-induced correlated phenomena beyond moir\'e systems.

Keywords

Cite

@article{arxiv.2602.16210,
  title  = {Stack of correlated insulating states in bilayer graphene kagome superlattice},
  author = {Xinyu Cai and Fengfan Ren and Qiao Li and Yanran Shi and Yifan Wang and Yifan Zhang and Zhenghang Zhi and Jiawei Luo and Yulin Chen and Jianpeng Liu and Xufeng Kou and Zhongkai Liu},
  journal= {arXiv preprint arXiv:2602.16210},
  year   = {2026}
}