skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Imaginary time density-density correlations for two-dimensional electron gases at high density

Abstract

We evaluate imaginary time density-density correlation functions for two-dimensional homogeneous electron gases of up to 42 particles in the continuum using the phaseless auxiliary field quantum Monte Carlo method. We use periodic boundary conditions and up to 300 plane waves as basis set elements. We show that such methodology, once equipped with suitable numerical stabilization techniques necessary to deal with exponentials, products, and inversions of large matrices, gives access to the calculation of imaginary time correlation functions for medium-sized systems. We discuss the numerical stabilization techniques and the computational complexity of the methodology and we present the limitations related to the size of the systems on a quantitative basis. We perform the inverse Laplace transform of the obtained density-density correlation functions, assessing the ability of the phaseless auxiliary field quantum Monte Carlo method to evaluate dynamical properties of medium-sized homogeneous fermion systems.

Authors:
;  [1];  [2];  [3]
  1. Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy)
  2. IOM-CNR DEMOCRITOS National Simulation Center and SISSA, Via Bonomea 265, 34136 Trieste (Italy)
  3. Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795 (United States)
Publication Date:
OSTI Identifier:
22493146
Resource Type:
Journal Article
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 143; Journal Issue: 16; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9606
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BOUNDARY CONDITIONS; CORRELATION FUNCTIONS; CORRELATIONS; DENSITY; FERMIONS; LAPLACE TRANSFORMATION; MONTE CARLO METHOD; STABILIZATION; WAVE PROPAGATION

Citation Formats

Motta, M., Galli, D. E., Moroni, S., and Vitali, E. Imaginary time density-density correlations for two-dimensional electron gases at high density. United States: N. p., 2015. Web. doi:10.1063/1.4934666.
Motta, M., Galli, D. E., Moroni, S., & Vitali, E. Imaginary time density-density correlations for two-dimensional electron gases at high density. United States. https://doi.org/10.1063/1.4934666
Motta, M., Galli, D. E., Moroni, S., and Vitali, E. 2015. "Imaginary time density-density correlations for two-dimensional electron gases at high density". United States. https://doi.org/10.1063/1.4934666.
@article{osti_22493146,
title = {Imaginary time density-density correlations for two-dimensional electron gases at high density},
author = {Motta, M. and Galli, D. E. and Moroni, S. and Vitali, E.},
abstractNote = {We evaluate imaginary time density-density correlation functions for two-dimensional homogeneous electron gases of up to 42 particles in the continuum using the phaseless auxiliary field quantum Monte Carlo method. We use periodic boundary conditions and up to 300 plane waves as basis set elements. We show that such methodology, once equipped with suitable numerical stabilization techniques necessary to deal with exponentials, products, and inversions of large matrices, gives access to the calculation of imaginary time correlation functions for medium-sized systems. We discuss the numerical stabilization techniques and the computational complexity of the methodology and we present the limitations related to the size of the systems on a quantitative basis. We perform the inverse Laplace transform of the obtained density-density correlation functions, assessing the ability of the phaseless auxiliary field quantum Monte Carlo method to evaluate dynamical properties of medium-sized homogeneous fermion systems.},
doi = {10.1063/1.4934666},
url = {https://www.osti.gov/biblio/22493146}, journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 16,
volume = 143,
place = {United States},
year = {Wed Oct 28 00:00:00 EDT 2015},
month = {Wed Oct 28 00:00:00 EDT 2015}
}