80 citations · 454 across the 13 of their papers we have counts for
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Accelerating Nonequilibrium Green functions simulations with embedding selfenergies
Karsten Balzer, Niclas Schlünzen, Hannes Ohldag +2
Real-time nonequilibrium Green functions (NEGF) have been very successful to simulate the dynamics of correlated many-particle systems far from equilibrium. However, NEGF simulatio…
The dynamically screened ladder approximation: Simultaneous treatment of strong electronic correlations and dynamical screening out of equilibrium
Jan-Philip Joost, Niclas Schlünzen, Hannes Ohldag +3
Dynamical screening is a key property of charged many-particle systems. Its theoretical description is based on the approximation that is extensively applied for ground-state…
Doublon production in correlated materials by multiple ion impacts
Lotte Borkowski, Niclas Schlünzen, Jan Philip Joost +2
In a recent Letter [Balzer \textit{et al.}, Phys. Rev. Lett. \textbf{121}, 267602 (2018)] it was demonstrated that ions impacting a correlated graphene cluster can excite strongly…
The G1--G2 Scheme: Dramatic Acceleration of Nonequilibrium Green Functions Simulations Within the Hartree--Fock-GKBA
J. -P. Joost, N. Schlünzen, M. Bonitz
The time evolution in quantum many-body systems after external excitations is attracting high interest in many fields. The theoretical modeling of these processes is challenging, a…
Ultrafast Dynamics of Strongly Correlated Fermions -- Nonequilibrium Green Functions and Selfenergy Approximations
N. Schluenzen, S. Hermanns, M. Scharnke +1
This article presents an overview on recent progress in the theory of nonequilibrium Green functions (NEGF). NEGF, presently, are the only \textit{ab-initio} quantum approach that…
Doublon formation by ions impacting a strongly correlated finite lattice system
Karsten Balzer, Maximilian Rodriguez Rasmussen, Niclas Schlünzen +2
Strongly correlated systems of fermions have a number of exciting collective properties. Among them, the creation of a lattice that is occupied by doublons, i.e. two quantum partic…
Nonequilibrium dynamics in the one-dimensional Fermi-Hubbard model: A comparison of the nonequilibrium Green functions approach and the density matrix renormalization group method
N. Schluenzen, J. -P. Joost, F. Heidrich-Meisner +1
The nonequilibrium dynamics of strongly-correlated fermions in lattice systems have attracted considerable interest in the condensed matter and ultracold atomic-gas communities. Wh…
Time Reversal Invariance of quantum kinetic equations: Nonequilibrium Green Functions Formalism
Miriam Scharnke, Niclas Schlünzen, Michael Bonitz
Time reversal symmetry is a fundamental property of many quantum mechanical systems. The relation between statistical physics and time reversal is subtle and not all statistical th…
Comment on "On the unphysical solutions of the Kadanoff--Baym equations in linear response: Correlation-induced homogeneous density-distribution and attractors"
N. Schlünzen, J. -P. Joost, M. Bonitz
In a recent Rapid Communication [A. Stan, Phys. Rev. B \textbf{93}, 041103(R) (2016)], the reliability of the Keldysh--Kadanoff--Baym equations (KBE) using correlated selfenergy ap…
Stopping dynamics of ions passing through correlated honeycomb clusters
Karsten Balzer, Niclas Schlünzen, Michael Bonitz
A combined nonequilibrium Green functions-Ehrenfest dynamics approach is developed that allows for a time-dependent study of the energy loss of a charged particle penetrating a str…
Toward a Nonequilibrium Green functions approach to diffusion in strongly coupled finite quantum systems
M. Bonitz, N. Schluenzen, S. Hermanns
Transport properties of strongly correlated quantum systems are of central interest in condensed matter, ultracold atoms and in dense plasmas. There, the proper treatment of strong…
Hubbard nanoclusters far from equilibrium
Sebastian Hermanns, Niclas Schlünzen, Michael Bonitz
The Hubbard model is a prototype for strongly correlated many-particle systems, including electrons in condensed matter and molecules, as well as for fermions or bosons in optical…