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arXiv · 1605.04589

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

A. A. Katanin·A. S. Belozerov·V. I. Anisimov
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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.

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A. A. Katanin, A. S. Belozerov, V. I. Anisimov. 2016-10-19. Nonlocal correlations in the vicinity of the $α$-$γ$ phase transition in iron within a DMFT plus spin-fermion model approach. https://doi.org/10.1103/physrevb.94.161117

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