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DOE OSTI · 2539969

Robust Biaxial Anisotropy and Switchable Néel Vectors in LaFeO 3 Epitaxial Films

Lanier, Joseph [The Ohio State University, Columbus, OH (United States)]·Michel, Justin [The Ohio State University, Columbus, OH (United States)]·Flores, Jose [The Ohio State University, Columbus, OH (United States)]·Yang, Fengyuan [The Ohio State University, Columbus, OH (United States)] (ORCID:0000000169211533)
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Abstract

Antiferromagnets with highly stable but switchable Néel vectors are desired for antiferromagnetic spintronics with ultrafast speed and terahertz frequencies. Electrical switching of antiferromagnetic insulators has been demonstrated using binary antiferromagnets, while large families of complex antiferromagnets such as perovskites are largely unexplored. Here, we show that epitaxial LaFeO 3 thin films on SrTiO 3 (001) exhibit clear, robust biaxial anisotropy with a spin-flop field of a few tesla. Angular-dependent spin-Hall magnetoresistance (SMR) characterizations of Pt/LaFeO 3 bilayers with the current channel along SrTiO 3 [100] and [110] reveal distinct, intriguing shapes and field dependence. Simulations using a macrospin model accurately describe the main behavior and fine features of the SMR data from which key antiferromagnetic parameters are extracted. Furthermore, remanent SMR measurement confirms the high fidelity of the Néel vector along either easy axis of the biaxial anisotropy, indicating that epitaxial films of LaFeO 3 and potentially other perovskite antiferromagnets offer an attractive platform for antiferromagnetic spintronics.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSantiferromagnetic insulatorbiaxial antiferromagnetic anisotropyepitaxial thin filmsepitaxymagnetic propertiesquantum mechanicsspin−Hall magnetoresistancethin filmsvesicles

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Lanier, Joseph [The Ohio State University, Columbus, OH (United States)], Michel, Justin [The Ohio State University, Columbus, OH (United States)], Flores, Jose [The Ohio State University, Columbus, OH (United States)], Yang, Fengyuan [The Ohio State University, Columbus, OH (United States)] (ORCID:0000000169211533). 2025-03-13. Robust Biaxial Anisotropy and Switchable Néel Vectors in LaFeO 3 Epitaxial Films. https://doi.org/10.1021/acs.nanolett.4c04810

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS subjectantiferromagnetic insulator subjectbiaxial antiferromagnetic anisotropy subjectepitaxial thin films subjectepitaxy subjectmagnetic properties subject

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