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arXiv · 2106.05715

Dynamical screening in SrVO$_3$: Inelastic x-ray scattering experiments and ab initio calculations

Kari Ruotsalainen·Alessandro Nicolaou·Christoph J. Sahle·Anna Efimenko·James M. Ablett·Jean-Pascal Rueff·Dharmalingam Prabhakaran·Matteo Gatti
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Abstract

We characterize experimentally and theoretically the high-energy dielectric screening properties of the prototypical correlated metal SrVO$_3$. The dynamical structure factor measured by inelastic x-ray scattering spectroscopy as a function of momentum transfer is in very good agreement with first-principles calculations in the adiabatic local density approximation to time-dependent density-functional theory. Our results reveal the crucial importance of crystal local fields in the charge response function of correlated materials: They lead to depolarization effects for localised excitations and couple spectra from different Brillouin zones.

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Kari Ruotsalainen, Alessandro Nicolaou, Christoph J. Sahle, Anna Efimenko, James M. Ablett, Jean-Pascal Rueff, Dharmalingam Prabhakaran, Matteo Gatti. 2021-06-10. Dynamical screening in SrVO$_3$: Inelastic x-ray scattering experiments and ab initio calculations. https://doi.org/10.1103/physrevb.103.235136

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