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arXiv · 2606.15548

Switching Chern number by sliding and gating in alternately twisted tetralayer MoTe2

Xiao-Wei Zhang·Kaijie Yang·Xiaodong Xu·Ting Cao·Di Xiao
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Abstract

Switching the bulk Chern number in topological materials is of central importance for the design of topological electronic devices. Motivated by recent observations of integer and fractional quantum anomalous Hall effects in twisted transition metal dichalcogenides (tTMDs), we realize the switching of valley Chern number through sliding and gating in alternately twisted tetralayer (ATT) MoTe$_{2}$. Using large-scale density functional theory (DFT) calculations, we show that the Chern number of the first $K$-valley moir\'e band evolves from $+1$ to $-1$ under the interlayer sliding. Furthermore, an applied electric field can switch the valley Chern number from $-1$ to $+1$. Based on the developed continuum model, we reveal that these switching behaviors are caused by the sliding- and gate-dependent intralayer moir\'e potential distributions across the layers. Our results establish ATT MoTe$_{2}$ as a promising platform for engineering moir\'e band topologies through the design of moir\'e potentials with sliding in multilayer moir\'e systems.

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Xiao-Wei Zhang, Kaijie Yang, Xiaodong Xu, Ting Cao, Di Xiao. 2026-06-14. Switching Chern number by sliding and gating in alternately twisted tetralayer MoTe2. https://arxiv.org/abs/2606.15548

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