Structure and strain tunings of topological anomalous Hall effect in cubic noncollinear antiferromagnet MnPt epitaxial films

Antiferromagnets (AFMs) with chiral noncollinear spin structure have attracted great attention in recent years. However, the existing research has mainly focused on hexagonal chiral AFMs, such as MnSn, MnGa, MnGe with low crystalline symmetry. Here, we present our systematical study for the face-centered cubic noncollinear antiferromagnetic MnPt. By varying the alloy composition (x), we have successfully fabricated antiferromagnetic MnPt epitaxial films on MgO substrates and have observed a crystalline structure transition from L1 MnPt to L1 MnPt. The MnPt exhibits a large anomalous Hall effect, which is in the same order of magnitude as those of ferromagnetic materials. Moreover, a large thickness-evolved strain effect is revealed in MnPt films by X-ray diffraction (XRD) analysis based on the Scherrer method. Our work explores MnPt as a promising candidate for topological antiferromagnetic spintronics.