Regensburg 2019 – wissenschaftliches Programm
TT 4.4: Vortrag
Montag, 1. April 2019, 10:15–10:30, H22
Non-equilibrium optical conductivity for the antiferromagnetic single-band Hubbard model: Time-dependent Gutzwiller analysis — •Christian Martens1, Jörg Bünemann2, and Götz Seibold1 — 1Institut für Physik, BTU Cottbus-Senftenberg, Postfach 101344, 03013 Cottbus, Germany — 2Fakultät Physik, TU Dortmund, 44227 Dortmund, Germany
Based on the time-dependent Gutzwiller approximation (TDGA) for the Hubbard model we analyze the optical conductivity σ(ω) in an out-of equilibrium situation for underlying antiferromagnetic ground states. The equilibrium state is perturbed by an instant quench of the local Coulomb interaction parameter U or by an electric field E(t). We analyze various shapes for the applied electric field and discuss our results with regard to the optical conductivity determination from pump-probe experiments. In the linear response regime, RPA corrections to the TDGA vanish, so that the optical response is determined by the bare current-current correlation function. In contrast, far from the linear response regime the out-of equilibrium case shows a more interesting behavior and in particular mixes double occupancy fluctuations to the current response.