Magnetic-field-induced robust zero Hall plateau state in MnBi₂Te₄ Chern insulator.

ABSTRACT: 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.

SUBMITTER: Liu C 

PROVIDER: S-EPMC8324822 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature