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arXiv · 1008.4621

Time-dependent second Born calculations for model atoms and molecules in strong laser fields

K. Balzer·S. Bauch·M. Bonitz
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Abstract

Using the finite-element discrete variable representation of the nonequilibrium Green's function (NEGF) we extend previous work [K.~Balzer et al., Phys. Rev. A \textbf{81}, 022510 (2010)] to nonequilibrium situations and compute---from the two-time Schwinger-Keldysh-Kadanoff-Baym equations---the response of the helium atom and the heteronuclear molecule lithium hydride to laser fields in the uv and xuv regime. In particular, by comparing the one-electron density and the dipole moment to time-dependent Hartree-Fock results on one hand and the full solution of the time-dependent Schrödinger equation on the other hand, we demonstrate that the time-dependent second Born approximation carries valuable information about electron-electron correlation effects. Also, we outline an efficient distributed memory concept which enables a parallel and well scalable algorithm for computing the NEGF in the two-time domain.

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K. Balzer, S. Bauch, M. Bonitz. 2010-08-27. Time-dependent second Born calculations for model atoms and molecules in strong laser fields. https://doi.org/10.1103/physreva.82.033427

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