Antiferromagnetic MnPt exhibits a spin reorientation transition (SRT) as a function of temperature, and offstoichiometric Mn-Pt alloys also display SRTs as a function of concentration. Here we describe the origin of these SRTs using first-principles calculations based on the coherent potential approximation, treating chemical and thermally-induced spin disorder on equal footing. We find that the experimentally observed SRTs are related to specific features in the band structure, and we perform a detailed analysis of the effects of temperature and concentration on the magnetocrystalline anisotropy.

Reference:
P.-H. Chang, T. Markussen, S. Smidstrup, K. Stokbro, and B.K. Nikolic, Phys. Rev. B 92, 201406(R) (2015).

J.M. Marmolejo-Tejada, K. Dolui, P. Lazic, P.-H. Chang, S. Smidstrup, D. Stradi, K. Stokbro, B.K. Nikolic, arXiv:1701.00462.