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arXiv · 2004.06677

Kondo screening in Co adatoms with full Coulomb interaction

Angelo Valli·Marc Philipp Bahlke·Alexander Kowalski·Michael Karolak·Carmen Herrmann·Giorgio Sangiovanni
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Abstract

Using a numerically exact first-principles many-body approach, we revisit the "prototypical" Kondo case of a cobalt impurity on copper. Even though this is considered a well understood example of the Kondo effect, we reveal an unexpectedly strong dependence of the screening properties on the parametrization of the local Coulomb tensor. As a consequence, the Kondo temperature can vary by orders of magnitude depending on the complexity of the parametrization of the electron-electron interaction. Further, we challenge the established picture of a spin-$1$ moment involving two cobalt $d$-orbitals only, as orbital-mixing interaction terms boost the contribution of the remainder of the $d$-shell.

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Angelo Valli, Marc Philipp Bahlke, Alexander Kowalski, Michael Karolak, Carmen Herrmann, Giorgio Sangiovanni. 2020-04-14. Kondo screening in Co adatoms with full Coulomb interaction. https://doi.org/10.1103/physrevresearch.2.033432

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