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arXiv · 2205.14795

Spin-orbit-derived giant magnetoresistance in a layered magnetic semiconductor AgCrSe2

Hidefumi Takahashi·Tomoki Akiba·Alex Hiro Mayo·Kazuto Akiba·Atsushi Miyake·Masashi Tokunaga·Hitoshi Mori·Ryotaro Arita·Shintaro Ishiwata
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Abstract

Two-dimensional magnetic materials have recently attracted great interest due to their unique functions as the electric field control of a magnetic phase and the anomalous spin Hall effect. For such remarkable functions, a spin-orbit coupling (SOC) serves as an essential ingredient. Here we report a giant positive magnetoresistance in a layered magnetic semiconductor AgCrSe2, which is a manifestation of the subtle combination of the SOC and Zeeman-type spin splitting. When the carrier concentration approaches the critical value of 2.5\times10^18 cm^-3, a sizable positive magnetoresistance of ~400 % emerges upon the application of magnetic fields normal to the conducting layers. Based on the magneto-Seebeck effect and the first-principles calculations, the unconventional magnetoresistance is ascribable to the enhancement of effective carrier mass in the SOC induced J = 3/2 state, which is tuned to the Fermi level through the Zeeman splitting enhanced by the p-d coupling. This study demonstrates a new aspect of the SOC-derived magnetotransport in two-dimensional magnetic semiconductors, paving the way to novel spintronic functions.

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Hidefumi Takahashi, Tomoki Akiba, Alex Hiro Mayo, Kazuto Akiba, Atsushi Miyake, Masashi Tokunaga, Hitoshi Mori, Ryotaro Arita, Shintaro Ishiwata. 2022-05-30. Spin-orbit-derived giant magnetoresistance in a layered magnetic semiconductor AgCrSe2. https://doi.org/10.1103/physrevmaterials.6.054602

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