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arXiv · 2106.03689

Fully {\it ab-initio} electronic structure of Ca$_{2}$RuO$_{4}$

Francesco Petocchi·Viktor Christiansson·Philipp Werner
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Abstract

The reliable {\it ab-initio} description of strongly correlated materials is a long-sought capability in condensed matter physics. The $GW$+EDMFT method is a promising scheme, which provides a self-consistent description of correlations and screening, and does not require user-provided parameters. In order to test the reliability of this approach we apply it to the experimentally well characterized perovskite compound Ca$_2$RuO$_4$, in which a temperature-dependent structural deformation drives a paramagnetic metal-insulator transition. Our results demonstrate that the nonlocal polarization and self-energy components introduced by $GW$ are essential for setting the correct balance between interactions and bandwidths, and that the $GW$+EDMFT scheme produces remarkably accurate predictions of the electronic properties of this strongly correlated material.

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Francesco Petocchi, Viktor Christiansson, Philipp Werner. 2021-06-07. Fully {\it ab-initio} electronic structure of Ca$_{2}$RuO$_{4}$. https://doi.org/10.1103/physrevb.104.195146

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