Diverse high-Chern-number quantum anomalous Hall insulators in twisted rhombohedral graphene

TL;DR

This paper demonstrates the realization of multiple high-Chern-number quantum anomalous Hall insulators in twisted rhombohedral graphene, revealing a highly tunable platform for dissipationless electronics and exotic quantum states.

Contribution

It reports the experimental observation of high-C QAH insulators with C=3,5,6,7 in twisted multilayer graphene, expanding the understanding of topological phases in moiré materials.

Findings

QAH effect with C=5 observed at 2K in twisted monolayer-rhombohedral pentalayer graphene.

High-C QAH insulators with C=3,6,7 identified at various fillings and twist angles.

Twisted rhombohedral multilayer graphene as a versatile platform for topological quantum states.

Abstract

Quantum anomalous Hall (QAH) insulators with high Chern number (C) enables multiple dissipationless edge channels for low-power-consumption electronics. We report the realization of multiple high-C QAH insulators including C=3,5,6, and 7 in twisted monolayer-rhombohedral pentalayer graphene. In twist angles of approximately 1.40{\deg}, we observe QAH effect with C=5 at a filling of one electron per moir\'e unit cell, persisting up to 2 Kelvin. Furthermore, incommensurate QAH insulators with C=5,6, and 7 emerge at partial fillings. In twist angles of 0.89{\deg}, Chern insulators with C=3 and C=6 appear at fillings of two and three electrons, respectively. Our findings establish twisted rhombohedral multilayer graphene as a highly tunable platform for multichannel, dissipationless electronics and for the exploration of exotic quantum Hall states beyond traditional Landau level paradigm.