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arXiv · 0910.2161

Orbital selective local moment formation in iron: first principle route to an effective model

A. A. Katanin·A. I. Poteryaev·A. V. Efremov·A. O. Shorikov·S. L. Skornyakov·M. A. Korotin·V. I. Anisimov
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Abstract

We revisit a problem of theoretical description of alpha-iron. By performing LDA+DMFT calculations in the paramagnetic phase we find that Coulomb interaction and, in particular Hund exchange, yields the formation of local moments in e_g electron band, which can be traced from imaginary time dependence of the spin-spin correlation function. This behavior is accompanied by non-Fermi-liquid behavior of e_g electrons and suggests using local moment variables in the effective model of iron. By investigating orbital-selective contributions to the Curie-Weiss law for Hund exchange I=0.9 eV we obtain an effective value of local moment of e_g electrons 2p=1.04 mu_B. The effective bosonic model, which allows to describe magnetic properties of iron near the magnetic phase transition, is proposed.

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A. A. Katanin, A. I. Poteryaev, A. V. Efremov, A. O. Shorikov, S. L. Skornyakov, M. A. Korotin, V. I. Anisimov. 2009-10-12. Orbital selective local moment formation in iron: first principle route to an effective model. https://doi.org/10.1103/physrevb.81.045117

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