Topological Hall effect in thin films of Mn_1.5PtSn

Abstract

Spin chirality in metallic materials with non-coplanar magnetic order can give rise to a Berry phase induced topological Hall effect. Here, we report the observation of a large topological Hall effect in high-quality films of Mn_1.5PtSn that were grown by means of magnetron sputtering on MgO(001). The topological Hall resistivity is present up to μ₀H≈4T below the spin reorientation transition temperature, T_s=185 K. We find that the maximum topological Hall resistivity is of comparable magnitude as the anomalous Hall resistivity. Owing to the size, the topological Hall effect is directly evident prior to the customarily performed subtraction of magnetometry data. Further, we underline the robustness of the topological Hall effect in Mn_2−xPtSn by extracting the effect for multiple stoichiometries (x=0.5,0.25,0.1) and film thicknesses (t=104,52,35 nm) with maximum topological Hall resistivities between 0.76 and 1.55μΩcm at 150 K.