Screening of a point charge: a fixed-node diffusion Monte Carlo study
Abstract
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 systems close to the Mott transition. As a specific application we discuss the implications of the efficient screening for the superconductivity in the doped Fullerenes. In the Monte Carlo calculations we use trial functions with two Gutzwiller-type parameters. To deal with such trial functions, we introduce a method for efficiently optimizing the Gutzwiller parameters, both in variational and in fixed-node diffusion Monte Carlo.
Cite
@article{arxiv.cond-mat/9904257,
title = {Screening of a point charge: a fixed-node diffusion Monte Carlo study},
author = {Erik Koch and Olle Gunnarsson and Richard M. Martin},
journal= {arXiv preprint arXiv:cond-mat/9904257},
year = {2007}
}
Comments
4 pages LaTeX with 4 eps figures; Computer Simulations Studies in Condensed Matter Physics XII, Eds.: D.P. Landau, S.P. Lewis, and H.B. Schuettler, Springer 1999; additional material available at http://www.mpi-stuttgart.mpg.de/docs/ANDERSEN/fullerene/