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arXiv · 2402.16104

Displaced Drude peak from $\pi$-ton vertex corrections

J. Krsnik·O. Simard·P. Werner·A. Kauch·K. Held
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Abstract

Correlated electron systems often show strong bosonic fluctuations, e.g., of antiferromagnetic nature, around a large wave vector such as $\mathbf{q}=(\pi,\pi\ldots)$. These fluctuations can give rise to vertex corrections to the optical conductivity through the (transversal) particle-hole channel, coined $\pi$-ton contributions. Previous numerical results differed qualitatively on how such vertex corrections alter the optical conductivity. Here, we clarify that $\pi$-ton vertex corrections lead to a displaced Drude peak for correlated metals. The proximity and enhancement of the effect when approaching a phase transition of, e.g., antiferromagnetic nature can be utilized for discriminating $\pi$-tons in experiments from other physics leading to a displaced Drude peak.

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J. Krsnik, O. Simard, P. Werner, A. Kauch, K. Held. 2024-02-25. Displaced Drude peak from $\pi$-ton vertex corrections. https://doi.org/10.1103/physrevb.110.075118

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