Engineering electrically-switchable quantum anomalous Hall states by spin-orbit coupling

Maosen Qin; Ziwei Wang; Gyeongmin Kim; Kenji Watanabe; Takashi Taniguchi; Steven H. Simon; Siddharth A. Parameswaran; Hryhoriy Polshyn

arXiv · 2606.13651

Engineering electrically-switchable quantum anomalous Hall states by spin-orbit coupling

Maosen Qin·Ziwei Wang·Gyeongmin Kim·Kenji Watanabe·Takashi Taniguchi·Steven H. Simon·Siddharth A. Parameswaran·Hryhoriy Polshyn

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Abstract

Nonvolatile gate-driven switching of quantum anomalous Hall (QAH) states in graphene moir\'e systems provides a promising route toward topological electronics based on chiral edge states. However, deliberate use of this switching mechanism requires control over both the magnetic properties and metastability of QAH states. While previous demonstrations mostly relied on the intrinsic magnetic energy landscape of moir\'e devices, here we show that this landscape can be engineered through proximity coupling to WSe2. We find that proximitizing twisted monolayer-bilayer graphene by WSe2 reshapes the magnetization reversals responsible for nonvolatile electrical switching of QAH states. We attribute this effect to the proximity-induced spin-orbit coupling (SOC), which can lock spin and valley and modify the magnetization of the competing states involved in switching compared with non-proximitized graphene systems. Our findings establish proximity-induced SOC as a new way to engineer magnetic properties and switchable magnetic states in graphene-based systems. We further demonstrate that strong magnetic metastability in tMBG allows the magnetic states to be gate-tuned between QAH and metallic regimes, and between QAH states with Chern numbers |C| = 2 and 1 without resetting the magnetic state. This functionality points toward new device architectures based on QAH chiral edge states.

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Maosen Qin, Ziwei Wang, Gyeongmin Kim, Kenji Watanabe, Takashi Taniguchi, Steven H. Simon, Siddharth A. Parameswaran, Hryhoriy Polshyn. 2026-06-11. Engineering electrically-switchable quantum anomalous Hall states by spin-orbit coupling. https://arxiv.org/abs/2606.13651

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