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Published on: May 27, 2020
Merging Features from Green's Functions and Time Dependent Density Functional Theory: A Route to the Description of
M Hopjan1, D Karlsson1, S Ydman1
1Mathematical Physics Division, Department of Physics, Lund University, 22100 Lund, Sweden; and European Theoretical Spectroscopy Facility (ETSF).
Abstract:
We propose a description of nonequilibrium systems via a simple protocol that combines exchange-correlation potentials from density functional theory with self-energies of many-body perturbation theory. The approach, aimed to avoid double counting of interactions, is tested against exact results in Hubbard-type systems, with respect to interaction strength, perturbation speed and inhomogeneity, and system dimensionality and size. In many regimes, we find significant improvement over adiabatic time dependent density functional theory or second Born nonequilibrium Green's function approximations. We briefly discuss the reasons for the residual discrepancies, and directions for future work.
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