Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
DY: Fachverband Dynamik und Statistische Physik
DY 38: Nonequilibrium Quantum Systems II (joint session TT/DY)
DY 38.5: Vortrag
Mittwoch, 11. März 2026, 16:00–16:15, HSZ/0105
Non-Local Correlation effects in DC and optical conductivity of the Hubbard model — Nagamalleswararao Dasari1, Hugo Strand2, Martin Eckstein1, Alexander Lichtenstein1, and •Evgeny Stepanov3 — 1Universität Hamburg, Germany — 2Örebro University, Sweden — 3CPHT, CNRS, École polytechnique, France
Many-body effects in correlated materials can be explored through various response functions, with transport measurements being among the simplest and most direct probes. Accurately addressing the unconventional transport properties of materials requires accounting for spatial electronic correlations. These correlations can significantly influence transport characteristics by modifying the electronic spectral function and giving rise to complex multi-electron scattering processes, known as vertex corrections, which can both strongly impact the conductivity. In this talk, I will discuss the impact of non-local correlations on the conductivity of the single-band Hubbard model within the recently developed D-GW method [arXiv:2507.16673]. I will demonstrate that the impact of non-local correlations on the conductivity differs between the correlated metallic and Mott insulating phases. Incorporating nonlocal correlations in both the electronic spectral function and vertex corrections is crucial for accurately describing the optical conductivity at finite frequencies in both these regimes. The crossover between the metallic and Mott insulating phases can be identified by a vanishing contribution of vertex corrections to the DC conductivity.
Keywords: Conductivity; Transport phenomena; Correlated systems; Time-dependent approach; Many-body calculations