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arXiv · 1312.3654

Impact of electronic correlations on the equation of state and transport in $\epsilon$-Fe

L. V. Pourovskii·J. Mravlje·M. Ferrero·O. Parcollet·I. A. Abrikosov
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Abstract

We have obtained the equilibrium volumes, bulk moduli, equations of state of the ferromagnetic cubic $\alpha$ and paramagnetic hexagonal $\epsilon$ phases of iron in close agreement with experiment using an ab initio dynamical mean-field theory approach. The local dynamical correlations are shown to be crucial for a successful description of the ground-state properties of paramagnetic $\epsilon$-Fe. Moreover, they enhance the effective mass of the quasiparticles and reduce their lifetimes across the $\alpha \to \epsilon$ transition leading to a step-wise increase of the resistivity, as observed in experiment. The calculated magnitude of the jump is significantly underestimated, which points to non-local correlations. The implications of our results for the superconductivity and non-Fermi-liquid behavior of $\epsilon$-Fe are discussed.

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L. V. Pourovskii, J. Mravlje, M. Ferrero, O. Parcollet, I. A. Abrikosov. 2013-12-12. Impact of electronic correlations on the equation of state and transport in $\epsilon$-Fe. https://doi.org/10.1103/physrevb.90.155120

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