$α$-FeSe as an orbital-selective incoherent metal: An LDA+DMFT study

L. Craco; M. S. Laad; S. Leoni

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arXiv · 0910.3828

$α$-FeSe as an orbital-selective incoherent metal: An LDA+DMFT study

L. Craco·M. S. Laad·S. Leoni

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Abstract

$α$-FeSe, a prototype iron-chalcogenide superconductor, shows clear signatures of a strange incoherent normal state. Motivated thereby, we use LDA+DMFT to show how strong multi-band correlations generate a low-energy pseudogap in the normal state, giving an incoherent metal in very good semi-quantitative agreement with observations. We interpret our results in terms of $α$-FeSe being close to Mottness. A wide range of anomalous responses in the "normal" state are consistently explained, lending strong support for this view. Implications for superconductivity arising from such an anomalous state are touched upon.

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L. Craco, M. S. Laad, S. Leoni. 2009-10-20. $α$-FeSe as an orbital-selective incoherent metal: An LDA+DMFT study. https://arxiv.org/abs/0910.3828

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