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arXiv · 2402.17832

Quantum anomalous Hall crystal at fractional filling of moir\'e superlattices

D. N. Sheng·Aidan P. Reddy·Ahmed Abouelkomsan·Emil J. Bergholtz·Liang Fu
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Abstract

We predict the emergence a state of matter with intertwined ferromagnetism, charge order and topology in fractionally filled moir\'e superlattice bands. Remarkably, these quantum anomalous Hall crystals exhibit a quantized integer Hall conductance that is different than expected from the filling and Chern number of the band. Microscopic calculations show that this phase is robustly favored at half-filling ($\nu=1/2$) at larger twist angles of the twisted semiconductor bilayer $t$MoTe$_2$

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D. N. Sheng, Aidan P. Reddy, Ahmed Abouelkomsan, Emil J. Bergholtz, Liang Fu. 2024-02-27. Quantum anomalous Hall crystal at fractional filling of moir\'e superlattices. https://doi.org/10.1103/physrevlett.133.066601

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