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arXiv · 2512.22576

Tunable Electronic Correlations in 135-Kagome Metals

Matteo Crispino·Niklas Witt·Stefan Enzner·Tommaso Gorni·Luca de' Medici·Domenico Di Sante·Giorgio Sangiovanni
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Abstract

Kagome metals exhibit rich correlated-electron physics, yet a systematic understanding of the degree of correlation across transition-metal species remains elusive. Using density-functional theory plus multi-orbital slave-spin mean-field theory, we investigate electronic correlations in the Ti-, V-, and Cr-based 135 compounds with Sb and Bi pnictogens. We find that the significantly stronger degree of correlation of the Cr-based materials compared to Ti and V can only be explained through the synergy of two effects: the larger electron filling of the $d$-shell and the reduced characteristic kinetic energy. We put forward that the substitution of Sb with Bi strengthens correlations in all compounds and make the prediction that the-yet-to-be-synthesized CsCr$_3$Bi$_5$ must be the most strongly correlated member of the entire family. These findings provide a quantitative, band-structure-based framework for understanding and predicting correlation strength in Kagome metals.

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Matteo Crispino, Niklas Witt, Stefan Enzner, Tommaso Gorni, Luca de' Medici, Domenico Di Sante, Giorgio Sangiovanni. 2025-12-27. Tunable Electronic Correlations in 135-Kagome Metals. https://arxiv.org/abs/2512.22576

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