Nonlocal correlations in the vicinity of the α-γ Phase transition in iron within a DMFT plus spin-fermion model approach

Abstract

We consider nonlocal correlations in iron in the vicinity of the α-γ phase transition within the spin rotationally invariant dynamical mean-field theory (DMFT) approach, combined with the recently proposed spin-fermion model of iron. The obtained nonlocal corrections to DMFT yield a decrease of the Curie temperature of the α phase, leading to an agreement with its experimental value. We show that the corresponding nonlocal corrections to the energy of the α phase are crucially important to obtain the proximity of energies of α and γ phases in the vicinity of the iron α-γ transformation. © 2016 American Physical Society.