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 Ag2CrO2. The material consists of two-dimensional triangular-lattice CrO2 layers with antiferromagnetically coupled S = 3/2 spins and Ag2 layers with high electrical conductivity. The butterfly-shaped MR appears only when the magnetic field is applied perpendicularly to the CrO2 plane with the maximum MR ratio (≈ 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 Ag2CrO2.
@article{arxiv.2008.09945,
title = {Butterfly-shaped magnetoresistance in triangular-lattice antiferromagnet Ag$_2$CrO$_2$},
author = {Hiroki Taniguchi and Mori Watanabe and Masashi Tokuda and Shota Suzuki and Eria Imada and Takashi Ibe and Tomonori Arakawa and Hiroyuki Yoshida and Hiroaki Ishizuka and Kensuke Kobayashi and Yasuhiro Niimi},
journal= {arXiv preprint arXiv:2008.09945},
year = {2020}
}