Tunable Quantum Anomalous Layer Hall Effect in Light-Irradiated van der Waals Antiferromagnets.

Tian, Yuping; Zhao, Chen-Hao; Zhang, Bin-Yuan; Kong, Xiangru; Gong, Wei-Jiang · Nano Lett · 2025

basic_science · Level V

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Abstract

The layer Hall effect (LHE), originating from layer-locked Berry curvature, extends the scope of the Hall effect family and offers promising prospects for quantum layertronics. Here, a light-induced quantum anomalous layer Hall effect (QALHE) in antiferromagnetically coupled van der Waals (vdW) multilayers is proposed. Within a hexagonal lattice model, circularly polarized light is found to enable precise control over the layer-locked Berry curvature distribution, which causes asynchronous quantum anomalous Hall effects (QAHEs) in distinct layers, manifested as layer-locked quantized Chern numbers. The interlayer asynchrony gives rise to a stepwise evolution of the total Chern number with an increase in light intensity. First-principles calculations confirm the QALHE in experimentally feasible VSi<sub>2</sub>N<sub>4</sub>/VSiGeN<sub>4</sub> heterobilayers, as well as in VSi<sub>2</sub>N<sub>4</sub> tri- and tetralayers, with Chern numbers up to 2, 3, and 4. Our findings bridge Floquet engineering with layer-locked transport phenomena, offering realistic pathways for nonequilibrium topological state manipulation in two-dimensional quantum materials.