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arXiv · 2210.11209

Hund bands in spectra of multiorbital systems

M. Środa·J. Mravlje·G. Alvarez·E. Dagotto·J. Herbrych
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Abstract

Spectroscopy experiments are routinely used to characterize the behavior of strongly correlated systems. An in-depth understanding of the different spectral features is thus essential. Here, we show that the spectrum of the multiorbital Hubbard model exhibits unique Hund \ms{bands} that occur at energies given only by the Hund coupling $J_\mathrm{H}$, as distinct from the Hubbard satellites following the interaction $U$. We focus on experimentally relevant single-particle and optical spectra that we calculate for a model related to iron chalcogenide ladders. The calculations are performed via the density-matrix renormalization group and Lanczos methods. The generality of the implications is verified by considering a generic multiorbital model within dynamical mean-field theory.

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M. Środa, J. Mravlje, G. Alvarez, E. Dagotto, J. Herbrych. 2022-10-20. Hund bands in spectra of multiorbital systems. https://doi.org/10.1103/physrevb.108.l081102

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