30 citations · 30 across the 2 of their papers we have counts for
6 papers
Renormalization of the electron-phonon coupling in the one-band Hubbard model
Erik Koch, Roland Zeyher
We investigate the effect of electronic correlations on the coupling of electrons to Holstein phonons in the one-band Hubbard model. We calculate the static electron-phonon vertex…
Field-doping of C60 crystals: A view form theory
Erik Koch, Olle Gunnarsson, Samuel Wehrli +1
The proposal of using the field-effect for doping organic crystals has raised enormous interest. To assess the feasibility of such an approach, we investigate the effect of a stron…
Decay properties of the density matrix and Wannier functions for interacting systems
S. Goedecker, E. Koch
For non-interacting electrons the one-particle density matrix and the related Wannier functions characterize a material as insulating or metallic. Introducing many-body Wannier fun…
Screening of a point charge: a fixed-node diffusion Monte Carlo study
Erik Koch, Olle Gunnarsson, Richard M. Martin
We study the static screening in a Hubbard-like model using fixed-node diffusion Monte Carlo. We find that the random phase approximation is surprisingly accurate even for metallic…
Fixed-node DMC for Fermions on a lattice: Application to the doped Fullerides
Erik Koch, Olle Gunnarsson, Richard M. Martin
Fullerides are crystals made from C60 molecules. When doped with alkali metals the valence electrons of the alkali atoms are transfered to the C60 molecules. We show how to set up…
Quantum Monte Carlo calculations for integer-doped Fullerides
Erik Koch, Olle Gunnarsson, Richard M. Martin
The doped Fullerides can be well described by a Hubbard model, which comprises the partly filled, threefold-degenerate t_1u orbital and the on-site Coulomb interaction U. The orbit…