The cubic ${\mathrm{Cu}}_3\mathrm{Au}$-type $X{\mathrm{Pt}}_3$ family ($X=\mathrm{V}$, Cr, and Mn) is a topological semimetal characterized by anticrossing gapped nodal lines near the Fermi level, which give rise to significant Berry curvatures and thus the to the anomalous Hall effect (AHE). Among the three members, ${\mathrm{CrPt}}_3$ has been experimentally verified to exhibit a large anomalous Hall conductivity (AHC), while its counterparts ${\mathrm{MnPt}}_3$ and ${\mathrm{VPt}}_3$ remain largely unexplored. Here, a series of ${\mathrm{MnPt}}_3$ thin films with varying thicknesses (20–70 nm) was epitaxially grown on the MgO substrates using magnetron sputtering and was systematically investigated by magnetization, electrical resistivity, and Hall resistivity measurements. ${\mathrm{MnPt}}_3$ films undergo a ferromagnetic transition at a Curie temperature $T_{\mathrm{C}}$, which increases as the film thickness increases, reaching $\sim 344$ K for the 70-nm-thick film. All the anomalous Hall transport properties of ${\mathrm{MnPt}}_3$ films, including the resistivity, conductivity, and angle, exhibit a strong correlation with their magnetic properties. The scaling analysis suggests that the intrinsic Berry-curvature mechanism dominates the observed AHE, while the extrinsic contributions are much smaller. The intrinsic AHC increases as the film thickness increases, while the extrinsic AHC is thickness independent. Such an enhanced intrinsic AHC in the ${\mathrm{MnPt}}_3$ films is most likely attributed to the strain effect, implying that it serves as an effective method to tune the electronic band topology in the $X{\mathrm{Pt}}_3$ topological semimetal.

Close

PrevNext

View figure in article

• Anomalous Hall effect
• Magnetism
• Spintronics
• Magnetic thin films
• Topological materials
• Sputtering
• Susceptibility measurements
• Transport techniques