Correlated electron systems often show strong bosonic fluctuations, e.g., of antiferromagnetic nature, around a large wave vector such as q=(π,π…). These fluctuations can give rise to vertex corrections to the optical conductivity through the (transversal) particle-hole channel, coined π-ton contributions. Previous numerical results differed qualitatively on how such vertex corrections alter the optical conductivity. Here, we clarify that π-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 π-tons in experiments from other physics leading to a displaced Drude peak.
@article{arxiv.2402.16104,
title = {Displaced Drude peak from $\pi$-ton vertex corrections},
author = {J. Krsnik and O. Simard and P. Werner and A. Kauch and K. Held},
journal= {arXiv preprint arXiv:2402.16104},
year = {2025}
}