Theoretical and experimental investigation of magnetic order in Mn₂PtIn

We present the results of a combined experimental and computational investigation of electronic, magnetic, and structural properties of Mn₂PtIn, a Heusler compound exhibiting tetragonal crystal structure and potential non-collinear magnetic order. Our calculations indicate that this alloy will likely crystallize in tetragonal structure with c/a ratio of around 1.3, although the cubic structure cannot be ruled out as well. The magnetic alignment that corresponds to the lowest energy tetragonal phase is non-collinear, with a large canting angle of around 30^o and a magnetization value of 0.70 µ_B/f.u. At the same time, in the cubic phase the magnetic alignment is ferrimagnetic, with a smaller magnetization value of around 0.30 µ_B/f.u. The non-collinearity in the tetragonal phase of Mn₂PtIn originates from the competition of nearest and next-nearest-plane exchange couplings. Experimentally, this material has been synthesized using the arc-melting technique. The x-ray diffraction pattern can be indexed with a tetragonal crystal structure (space group I-4m2). The unit cell parameters, determined from Rietveld refinement, are a = b = 4.323 Å and c = 6.743 Å. In the thermomagnetic curve, a magnetic transition is observed near 350 K. Magnetization isotherms reveal high-field (3T) magnetization values of 1.28 μ_B/f.u. at 100 K and 0.57 μ_B/f.u. at 300 K. We will also discuss the electrical transport properties of the arc-melted bulk Mn₂PtIn in this presentation.