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arXiv · 2203.01273

Nematic spectral signatures of the Hund's metal

Laura Fanfarillo·Angelo Valli·Massimo Capone
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Abstract

We show, by means of dynamical mean-field theory calculations, that the experimental fingerprints of the nematic order in iron-based superconductors are intrinsically connected with the electronic correlations in the Hund's correlated metallic state and they can not be accessed via a renormalized quasiparticle picture. In particular, our results show that: (i) in a metal in which correlations are dominated by the Hund's coupling the nematic ordering does not produce a rigid energy shift in the photoemission spectra, but a much richer spectral weight redistribution which mirrors the experimental results; (ii) the nematic ordering is characterized by an orbital-selective coherence induced by the Hund's physics in agreement with the experimental picture.

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Laura Fanfarillo, Angelo Valli, Massimo Capone. 2022-03-02. Nematic spectral signatures of the Hund's metal. https://doi.org/10.1103/physrevb.107.l081114

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