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arXiv · 1912.11964

Ferromagnetic state above room temperature in a proximitized topological Dirac semimetal

Masaki Uchida·Takashi Koretsune·Shin Sato·Markus Kriener·Yusuke Nakazawa·Shinichi Nishihaya·Yasujiro Taguchi·Ryotaro Arita·Masashi Kawasaki
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Abstract

We report an above-room-temperature ferromagnetic state realized in a proximitized Dirac semimetal, which is fabricated by growing typical Dirac semimetal Cd$_3$As$_2$ films on a ferromagnetic garnet with strong perpendicular magnetization. Observed anomalous Hall conductivity with substantially large Hall angles is found to be almost proportional to magnetization and opposite in sign to it. Theoretical calculations based on first-principles electronic structure also demonstrate that the Fermi-level dependent anomalous Hall conductivity reflects the Berry curvature originating in the split Weyl nodes. The present Dirac-semimetal/ferromagnetic-insulator heterostructure will provide a novel platform for exploring Weyl-node transport phenomena and spintronic functions lately proposed for topological semimetals.

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Masaki Uchida, Takashi Koretsune, Shin Sato, Markus Kriener, Yusuke Nakazawa, Shinichi Nishihaya, Yasujiro Taguchi, Ryotaro Arita, Masashi Kawasaki. 2019-12-27. Ferromagnetic state above room temperature in a proximitized topological Dirac semimetal. https://doi.org/10.1103/physrevb.100.245148

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