Dresden 2026 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 23: Correlated Electrons – Poster I
TT 23.24: Poster
Monday, March 9, 2026, 18:00–20:00, P1
DMFT-Lanczos study of Alkali-Doped Fullerides: Superconductivity across the (U,J) plane — •Lara Bremer, Lorenzo Crippa, Igor Krivenko, and Tim O. Wehling — I. Institute of Theoretical Physics, University of Hamburg, Notkestraße 9-11, 22607 Hamburg
Alkali-doped fullerides (A3C60) provide a versatile platform for studying unconventional s-wave superconductivity in a strongly correlated setting, where superconducting phases emerge in close proximity to Mott insulating states. These molecular superconductors exhibit critical temperatures up to about 40 K. Theoretical descriptions of alkali-doped fullerides commonly employ a three-orbital Hubbard-Kanamori model whose defining feature is an effective negative Hund’s coupling arising from the coupling of the electronic states to intramolecular Jahn-Teller phonon modes, thereby reversing the usual Hund’s rules.
In this contribution we present calculations performed with the multi-orbital Lanczos impurity solver of the EDIpack library within a dynamical mean-field theory framework. We explore the (U,J) interaction space, focusing on the evolution from the regime of weak negative Hund’s coupling to regimes with strongly negative Hund’s coupling. We analyze how the interplay between the Mott insulating phase present for large Hubbard interaction U and the charge-disproportionated insulating phase present for large negative values of J influences the character of the superconducting states and ehances critical temperatures.
Keywords: alkali-doped fullerides; Dynamical Mean Field Theory; superconductivity; Lanczos; correlated electrons