Magnetic properties and anomalous Hall effect in antiferromagnetic Mn3Sn films

Abstract

Antiferromagnetic polycrystalline Mn3Sn thin films with different thicknesses were prepared using DC magnetron sputtering. The magnetic properties, anomalous Hall effect (AHE), and the correlation between them were investigated. X-ray diffraction measurements show that a small amount of ferromagnetic Mn2Sn phase coexisted with antiferromagnetic Mn3Sn. The films exhibited weak ferromagnetic behavior at room temperature due to the tilt of Mn spin magnetic moment of the antiferromagnetic Mn3Sn. The saturation magnetization notably increased below 250 K, corresponding to the Curie temperature of Mn2Sn. The Hall resistance curve and magnetic analysis indicate that AHE of antiferromagnetic Mn3Sn was completely different from that of a ferromagnetic metal, i.e., AHE resulted from the non-zero Berry curvature of momentum space and the ferromagnetism is not required to AHE. These findings can promote the applications of Mn3Sn thin films in the antiferromagnetic spintronic devices.