40 citations · 427 across the 32 of their papers we have counts for
5 papers · 1 filter
Light-matter hybrid-orbital-based first-principles methods: the influence of the polariton statistics
Florian Buchholz, Iris Theophilou, Klaas J. H. Giesbertz +2
A detailed understanding of strong matter-photon interactions requires first-principle methods that can solve the fundamental Pauli-Fierz Hamiltonian of non-relativistic quantum el…
Invertibility of the retarded response functions for initial mixed states: application to one-body reduced density matrix functional theory
Klaas J. H. Giesbertz
In [J. Chem. Phys. 143, 054102 (2015)] I have derived conditions to characterize the kernel of the retarded response function, under the assumption that the initial state is a grou…
Invertibility of retarded response functions for Laplace transformable potentials: application to one-body reduced density matrix functional theory
Klaas J. H. Giesbertz
A theorem for the invertibility of arbitrary response functions is presented under the following conditions: the time-dependence of the potentials should be Laplace transformable a…
Are natural orbitals useful for generating an efficient expansion of the wave function?
Klaas J. H. Giesbertz
We investigate whether the natural orbitals (NOs) minimize , where is a wave function and is a full configuration interaction (CI) approximation to …
Density-potential mappings in quantum dynamics
M. Ruggenthaler, K. J. H Giesbertz, M. Penz +1
In a recent letter [Europhys. Lett. 95, 13001 (2011)] the question of whether the density of a time-dependent quantum system determines its external potential was reformulated as a…