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arXiv · 2301.08927

Discovery of a magnetic Dirac system with large intrinsic non-linear Hall effect

Federico Mazzola·Barun Ghosh·Jun Fujii·Gokul Acharya·Debashis Mondal·Giorgio Rossi·Arun Bansil·Daniel Farias·Jin Hu·Amit Agarwal·Antonio Politano·Ivana Vobornik
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Abstract

Magnetic materials exhibiting topological Dirac fermions are attracting significant attention for their promising technological potential in spintronics. In these systems, the combined effect of the spin-orbit coupling and magnetic order enables the realization of novel topological phases with exotic transport properties, including the anomalous Hall effect and magneto-chiral phenomena. Herein, we report experimental signature of topological Dirac antiferromagnetism in TaCoTe2 via angle-resolved photoelectron spectroscopy (ARPES) and first-principles density functional theory (DFT) calculations. In particular, we find the existence of spin-orbit coupling-induced gaps at the Fermi level, consistent with the manifestation of a large intrinsic non-linear Hall conductivity. Remarkably, we find that the latter is extremely sensitive to the orientation of the N\'eel vector, suggesting TaCoTe2 a suitable candidate for the realization of non-volatile spintronic devices with an unprecedented level of intrinsic tunability.

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Federico Mazzola, Barun Ghosh, Jun Fujii, Gokul Acharya, Debashis Mondal, Giorgio Rossi, Arun Bansil, Daniel Farias, Jin Hu, Amit Agarwal, Antonio Politano, Ivana Vobornik. 2023-01-21. Discovery of a magnetic Dirac system with large intrinsic non-linear Hall effect. https://doi.org/10.1021/acs.nanolett.2c04194

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