Nonequilibrium electron dynamics in dense plasmas including dynamical screening and strong coupling

The Nonequilibrium Green Functions (NEGF) method is a powerful tool to compute time-dependent expectation values of single-particle observables in correlated quantum many-body systems. Its unfavorable $N_t^3$-scaling with propagation time $N_t$ could be reduced to $N_t^2$ by introduction of the Generalized Kadanoff--Baym Ansatz (GKBA)[1]. Recently, an exact time-local ($N_t^1$) reformulation of the GKBA, the G1--G2 scheme [2,3], has been found for various self energies, which makes this method viable for long time simulations.\\ In a general basis the G1--G2 scheme has a computationally expensive scaling with basis size ($N_b^5$-$N_b^6$). For the uniform electron gas (UEG) however, we found an advantageous $N_b^3 N_t^1$ scaling for both second-order and GW selfenergies, which makes this scheme particularly interesting for this system. Here, we present first relaxation results in 1 and 2 dimensions.\\ \quad [1] P. Lipavsk\'y, V. \v{S}pi\v{c}ka, Velick\'y, B, \textit{Phys. Rev. B}34, 6933 (1986)\\ \quad [2] N. Schl\"unzen, Jan-Philip Joost, Michael Bonitz, \textit{Phys. Rev. Lett.} 124, 076601 (2020)\\ \quad [3] M. Bonitz, \textit{Quantum Kinetic Theory} (Springer, 2016)