DCMP Seminar: Anna Kauch

Department of Condensed Matter Physics invites you to lecture

Anna Kauch (Institute of Solid State Physics, Technische Universität Wien, Rakousko):
Displaced Drude peak from vertex corrections to optical conductivity in correlated metals

Susceptibilities and optical conductivity are examples of two-particle response functions that are the key quantities for connecting theoretical predictions with experimental results. It can however become highly non-trivial to calculate them, especially in cases when vertex corrections are important. In my talk I will explain what vertex corrections to response functions are and when they become important. I will then present diagrammatic methods of their computation with the focus on parquet equations. I will show results for a special type of vertex corrections to optical conductivity, the pi-tons [1], that are present in systems with antiferromagnetic or charge density wave fluctuations. These vertex corrections lead to a displaced Drude peak in correlated metals [2].

[1] A. Kauch, P. Pudleiner, K. Astleithner, P.Thunström, T. Ribic, K. Held, Phys. Rev. Lett. 124, 047401 (2020).
[2] J. Krsnik, O. Simard, P. Werner, A. Kauch and K. Held, Phys. Rev. B 110, 075118 (2024).