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arXiv · 2008.09945

Butterfly-shaped magnetoresistance in triangular-lattice antiferromagnet Ag$_2$CrO$_2$

Hiroki Taniguchi·Mori Watanabe·Masashi Tokuda·Shota Suzuki·Eria Imada·Takashi Ibe·Tomonori Arakawa·Hiroyuki Yoshida·Hiroaki Ishizuka·Kensuke Kobayashi·Yasuhiro Niimi
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Abstract

Spintronic devices using antiferromagnets (AFMs) are promising candidates for future applications. Recently, many interesting physical properties have been reported with AFM-based devices. Here we report a butterfly-shaped magnetoresistance (MR) in a micrometer-sized triangular-lattice antiferromagnet Ag$_2$CrO$_2$. The material consists of two-dimensional triangular-lattice CrO$_2$ layers with antiferromagnetically coupled $S$ = 3/2 spins and Ag$_2$ layers with high electrical conductivity. The butterfly-shaped MR appears only when the magnetic field is applied perpendicularly to the CrO$_2$ plane with the maximum MR ratio ($\approx$ 15%) at the magnetic ordering temperature. These features are distinct from those observed in conventional magnetic materials. We propose a theoretical model where fluctuations of partially disordered spins with the Ising anisotropy play an essential role in the butterfly-shaped MR in Ag$_2$CrO$_2$.

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Hiroki Taniguchi, Mori Watanabe, Masashi Tokuda, Shota Suzuki, Eria Imada, Takashi Ibe, Tomonori Arakawa, Hiroyuki Yoshida, Hiroaki Ishizuka, Kensuke Kobayashi, Yasuhiro Niimi. 2020-08-23. Butterfly-shaped magnetoresistance in triangular-lattice antiferromagnet Ag$_2$CrO$_2$. https://doi.org/10.1038/s41598-020-59578-z

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