https://doi.org/10.1140/epjb/s10051-025-00938-x
Regular Article - Mesoscopic and Nanoscale Systems
Short-time character of corrections to the generalized Kadanoff–Baym Ansatz
1
Institute of Physics, Czech Academy of Sciences, 18200, Praha 8, Czech Republic
2
Faculty of Mathematics and Physics, Charles University, 12116, Praha 2, Czech Republic
Received:
18
February
2025
Accepted:
23
April
2025
Published online:
7
May
2025
An approximation of the Green function based on the Generalized Kadanoff–Baym Ansatz and its correction is tested on the electron tunneling through a single atom, incorporating the on-site second-order Born interaction. Time evolution resulting from the corresponding kinetic equation for the density matrix is compared with the direct solution of the non-equilibrium Green functions. It is demonstrated that the short-time nature of corrections beyond the Generalized Kadanoff–Baym Ansatz enables their effective numerical approximation.
© The Author(s) 2025
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