Complex magnetic phase diagram of metamagnetic MnPtSi

Abstract

The magnetic, thermal and transport properties as well as electronic band structure of MnPtSi are reported. MnPtSi is a metal that undergoes a ferromagnetic transition at $T_{\mathrm{C}}=340$(1) K and a spin-reorientation transition at $T_{\mathrm{N}}=326$(1) K to an antiferromagnetic phase. First-principles electronic structure calculations indicate a not-fully polarized spin state of Mn in a $d^5$ electron configuration with $J=S=3$/2, in agreement with the saturation magnetization of 3~${\mu }_{\mathrm{B}}$ in the ordered state and the observed paramagnetic effective moment. A sizeable anomalous Hall effect in the antiferromagnetic phase alongside the computational study suggests that the antiferromagnetic structure is non-collinear. Based on thermodynamic and resistivity data we construct a magnetic phase diagram. Magnetization curves $M$($H$) at low temperatures reveal a metamagnetic transition of spin-flop type. The spin-flopped phase terminates at a critical point with $T_{\mathrm{cr}}\approx 300$ K and $H_{\mathrm{cr}}\approx 10$ kOe, near which a peak of the magnetocaloric entropy change is observed. Using Arrott plot analysis and magnetoresistivity data we argue that the metamagnetic transition is of a first-order type, whereas the strong field dependence of $T_{\mathrm{N}}$ and the linear relationship of the $T_{\mathrm{N}}$ with $M^2$ hint at its magnetoelastic nature.

References in corpus (18)

• Anomalous Hall effect
• Topological Hall effect in the A-phase of MnSi
• Emergent electrodynamics of skyrmions in a chiral magnet
• Large anomalous Hall effect driven by non-vanishing Berry curvature in non-collinear antiferromagnetic Mn3Ge
• Anomalous Hall effect arising from noncollinear antiferromagnetism
• Berry Phase Theory of Anomalous Hall Effect: Application to Colossal Magnetoresistance Manganites
• Topological Hall effect and Berry phase in magnetic nanostructures
• Anomalous Hall Effect in Weyl Metals
• Orbital ferromagnetism and anomalous Hall effect in antiferromagnets on distorted fcc lattice
• Negative magnetocaloric effect from highly sensitive metamagnetism in CoMnSi_{1-x}Ge_{x}
• Giant magneto-elastic coupling in a metallic helical metamagnet
• Exploring the spin-1/2 frustrated square lattice model with high-field magnetization measurements
• Structurally driven metamagnetism in MnP and related Pnma compounds
• Designed Metamagnetism in CoMnGe_{1-x}P_{x}
• Magneto-elastic coupling and competing entropy changes in substituted CoMnSi metamagnets
• Structural and magnetic properties of MnCo1-xFexSi alloys
• Magnetocaloric effect and nature of magnetic transition in nanoscale Pr0.5Ca0.5MnO3
• Pressure Tuning of Collapse of Helimagnetic Structure in Au${}_2$Mn