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arXiv · 2301.04908

Diagnostics for plasmon satellites and Hubbard bands in transition metal oxides

Abstract

Coulomb correlations between the electrons imprint characteristic signatures to the spectral properties of materials. Among others, they are at the origin of a rich phenomenology of satellite features, either stemming from atomic-like multiplets or from interactions with particle-hole excitations or plasmons. While in many cases the latter lie at considerably higher energies than the former, suggesting clear distinction criteria, this picture has recently become blurred by indications that satellites of different types can coexist in the same energy range. It is now generally accepted that the identification of the nature of spectral features is a highly non-trivial task. In this article we propose a general procedure for tracing the origin of satellites of different types within modern ab initio calculations. As an illustration, we analyze the ternary transition metal oxides SrVO$_3$ and SrMoO$_3$, which are drosophila compounds for the coexistence of Hubbard and plasmonic satellites, reconciling previous seemingly contradictory findings in an unexpected manner.

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Steffen Backes, Hong Jiang, Silke Biermann. 2023-01-12. Diagnostics for plasmon satellites and Hubbard bands in transition metal oxides. https://arxiv.org/abs/2301.04908

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