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arXiv · 2504.03892

Anisotropic Field Suppression of Morin Transition Temperature in Epitaxially Grown Hematite Thin Films

Haoyu Liu·Hantao Zhang·Josiah Keagy·Qinwu Gao·Letian Li·Junxue Li·Ran Cheng·Jing Shi
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Abstract

We have demonstrated the existence of the Morin transition in epitaxially grown hematite thin films exceeding a critical thickness. The Morin transition temperature can be suppressed by magnetic fields applied both parallel and perpendicular to the Dzyaloshinskii-Moriya (DM) vector, exhibiting a distinct anisotropic behavior that is consistent with bulk hematite crystals. Detailed analysis explains the anisotropic behavior and provides a method for determining the DM strength, which remains nearly constant across the sample thickness over four orders of magnitude. Our findings obtained with transport measurements offer a valuable approach for studying antiferromagnetic spin configurations in thin films and nanodevices.

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Haoyu Liu, Hantao Zhang, Josiah Keagy, Qinwu Gao, Letian Li, Junxue Li, Ran Cheng, Jing Shi. 2025-04-04. Anisotropic Field Suppression of Morin Transition Temperature in Epitaxially Grown Hematite Thin Films. https://doi.org/10.1103/physrevmaterials.9.034410

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