Finite elements and the discrete variable representation in nonequilibrium Green's function calculations. Atomic and molecular models
Abstract
In this contribution, we discuss the finite-element discrete variable representation (FE-DVR) of the nonequilibrium Green's function and its implications on the description of strongly inhomogeneous quantum systems. In detail, we show that the complementary features of FEs and the DVR allows for a notably more efficient solution of the two-time Schwinger/Keldysh/Kadanoff-Baym equations compared to a general basis approach. Particularly, the use of the FE-DVR leads to an essential speedup in computing the self-energies. As atomic and molecular examples we consider the He atom and the linear version of H in one spatial dimension. For these closed-shell models we, in Hartree-Fock and second Born approximation, compute the ground-state properties and compare with the exact findings obtained from the solution of the few-particle time-dependent Schr\"odinger equation.
Cite
@article{arxiv.0911.4348,
title = {Finite elements and the discrete variable representation in nonequilibrium Green's function calculations. Atomic and molecular models},
author = {Karsten Balzer and Sebastian Bauch and Michael Bonitz},
journal= {arXiv preprint arXiv:0911.4348},
year = {2015}
}
Comments
12 pages, 3 figures, submitted as proceedings of conference "PNGF IV"