The intrinsic antiferromagnetic topological insulator MnBi₂Te₄ provides an ideal platform for exploring exotic topological quantum phenomena. Recently, the Chern insulator and axion insulator phases have been realized in few-layer MnBi₂Te₄ devices at low magnetic field regime. However, the fate of MnBi₂Te₄ in high magnetic field has never been explored in experiment. In this work, we report transport studies of exfoliated MnBi₂Te₄ flakes in pulsed magnetic fields up to 61.5 T. In the high-field limit, the Chern insulator phase with Chern number C = −1 evolves into a robust zero Hall resistance plateau state. Nonlocal transport measurements and theoretical calculations demonstrate that the charge transport in the zero Hall plateau state is conducted by two counter-propagating edge states that arise from the combined effects of Landau levels and large Zeeman effect in strong magnetic fields. Our result demonstrates the intricate interplay among intrinsic magnetic order, external magnetic field, and nontrivial band topology in MnBi₂Te₄.

本征反铁磁拓扑绝缘体MnBi ₂ Te ₄为探索奇异的拓扑量子现象提供了理想的平台。最近，陈绝缘体和轴子绝缘体相已在低磁场条件下的少层MnBi ₂ Te ₄器件中实现。然而，MnBi ₂ Te ₄在强磁场中的命运从未在实验中得到探索。在这项工作中，我们报告了剥离的 MnBi ₂ Te ₄薄片在高达 61.5 T 的脉冲磁场中的输运研究。在高场极限下，陈数C = -1 的陈绝缘体相演变成稳健的零霍尔电阻平台状态。非局域输运测量和理论计算表明，零霍尔平台态的电荷输运是由两个反向传播的边缘态进行的，这两个边缘态是由朗道能级和强磁场中大塞曼效应的综合效应产生的。我们的结果证明了 MnBi ₂ Te ₄中固有磁序、外部磁场和非平凡能带拓扑之间复杂的相互作用。