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arXiv · 1505.02055

Electronic structure of CeRu4Sn6: a density functional plus dynamical mean field theory study

P. Wissgott·K. Held
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Abstract

The Kondo system CeRu$_4$Sn$_6$ shows a strong anisotropy in its electric, optic and magnetic properties. We employ density functional theory plus dynamical mean field theory and show that the predominant Ce-$f$ state has total angular moment $J=5/2$ and $z$-component $m_J=\pm 1/2$ in agreement with recent X-ray absorption experiments. Even though CeRu$_4$Sn$_6$ has the direct gap of a Kondo insulator through most of the Brillouin zone it remains weakly metallic. This is because of (i) a band crossing in the $z$-direction and (ii) a negative indirect gap.

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P. Wissgott, K. Held. 2015-05-08. Electronic structure of CeRu4Sn6: a density functional plus dynamical mean field theory study. https://doi.org/10.1140/epjb%2Fe2015-60753-5

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