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arXiv · 2411.19898

Anti-topological crystal and non-Abelian liquid in twisted semiconductor bilayers

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

We show that electron crystals compete closely with non-Abelian fractional Chern insulators in the half-filled second moir\'e band of twisted bilayer MoTe$_2$. Depending on the twist angle and microscopic model, these crystals can have non-zero or zero Chern numbers $C$. The $C=0$ crystal occurs because contributions to the total Chern number from the full first band (+1) and half-full second band (-1) cancel. This is counterintuitive because the first two non-interacting bands in a given valley have the same Chern number $+1$. For these two reasons, we call this crystal an anti-topological crystal. The anti-topological crystal is a novel type of electron crystal that may occur in systems with multiple Chern bands at filling factors $n>1$.

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Aidan P. Reddy, D. N. Sheng, Ahmed Abouelkomsan, Emil J. Bergholtz, Liang Fu. 2024-11-29. Anti-topological crystal and non-Abelian liquid in twisted semiconductor bilayers. https://doi.org/10.1038/s41467-026-70916-z

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