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arXiv · 2605.02119

Metastable MnBi$_2$Te$_4$ enabled by magnetic-field-assisted synthesis

Abhinna Rajbanshi·G. M. Zills·Alexander M. Donald·Daniel Duong·David Graf·James J. Hamlin·Mark W. Meisel·I. Vekhter·Williams A. Shelton·Rongying Jin
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Abstract

Magnetic topological insulators provide a unique platform to explore the interplay between magnetism and topology. MnBi$_2$Te$_4$, known for its A-type antiferromagnetic (AFM) ground state, undergoes a striking transformation when single crystals are grown in an applied magnetic field. Despite retaining the same crystal structure, field-grown MnBi$_2$Te$_4$ exhibits a ferromagnetic (FM) ground state with a Curie temperature of $\sim$ 12.5 K, confirmed by magnetization, magnetic torque, electrical resistivity, and specific heat measurements. First-principles calculations support these findings, revealing that magnetic-field-assisted synthesis can effectively reconfigure the ground-state spin order and thereby modify the material's electronic properties, as reflected in the de Haas-van Alphen oscillation seen in the magnetic torque.

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Abhinna Rajbanshi, G. M. Zills, Alexander M. Donald, Daniel Duong, David Graf, James J. Hamlin, Mark W. Meisel, I. Vekhter, Williams A. Shelton, Rongying Jin. 2026-05-04. Metastable MnBi$_2$Te$_4$ enabled by magnetic-field-assisted synthesis. https://arxiv.org/abs/2605.02119

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