Initial correlated states for the generalized Kadanoff–Baym Ansatz without adiabatic switching-on of interactions in closed systems
Department of Physics and European Theoretical Spectroscopy Facility (ETSF), Lund University,
P.O. Box 118,
221 00 Lund, Sweden
a e-mail: email@example.com
Received in final form: 18 June 2018
Published online: 18 January 2019
We reconsider the Generalized Kadanoff–Baym Ansatz (GKBA) approximation for non-equilibrium Green’s functions and extend it to self-consistently define an equilibrium correlated (within GKBA) state in closed systems. The advantage of the proposed prescription is to avoid the preparation of the initial equilibrium correlated state via adiabatic switching-on of the correlations. A simple model system, namely a Hubbard-dimer, is used to illustrate aspects of the computational implementation and performance of the new scheme.
© The Author(s) 2019
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