Spin-valve like magnetoresistance and moderate anomalous Hall effect in CoRuMnSn

We report CoRuMnSn as a candidate material for spin-valve like features and moderate anomalous Hall effect, based on combined experimental and theoretical studies. It crystallizes in the F43m space group with a 12.5% disorder between the Ru and Mn atoms, exhibiting a magnetic moment of 3.53 µB/f.u. and a high Curie temperature (∼400 K). The magnetoresistance (MR) varies asymmetrically with field, indicating spin-valve like behavior. The anomalous Hall conductivity (AHC) remains nearly constant (∼ -390 S/cm at 2K) across a wide temperature (T) range and the weak T-dependence of Hall resistivity suggests an intrinsic AHC mechanism. Ab-initio calculations of electronic, magnetic, and transport properties agree well with experimental results. The band structure of ordered CoRuMnSn hosts four pairs of Weyl points, contributing intrinsic Berry curvature to AHC (∼ -371 S/cm). Simulations of experimentally observed Ru-Mn antisite disorder reveal pinning of those Mn atoms sitting at Ru sites, aligned antiferromagnetically with others, thus reducing the net magnetization (3.69 µB/f.u.), consistent with experiment. This pinning creates domains with antiferromagnetic/ferromagnetic interfaces, explaining the large asymmetric MR, supported by our magnetic force microscopy.