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arXiv · 1206.0569

Microscopic origin of the linear temperature increase of the magnetic susceptibility of BaFe$_{2}$As$_{2}$

S. L. Skornyakov·V. I. Anisimov·D. Vollhardt
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Abstract

Employing a combination of \emph{ab initio} band structure theory and dynamical mean-field theory we explain the experimentally observed linear temperature increase of the magnetic susceptibility of the iron pnictide material BaFe$_{2}$As$_{2}$. The microscopic origin of this anomalous behaviour is traced to a sharp peak in the spectral function located approximately 100 meV below the Fermi level. This peak is due to the weak dispersion of two-dimensional bands associated with the layered crystal structure of pnictides.

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S. L. Skornyakov, V. I. Anisimov, D. Vollhardt. 2012-06-04. Microscopic origin of the linear temperature increase of the magnetic susceptibility of BaFe$_{2}$As$_{2}$. https://doi.org/10.1103/physrevb.86.125124

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