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Title: Quantum Monte Carlo simulation in the canonical ensemble at finite temperature

Abstract

A quantum Monte Carlo method with a nonlocal update scheme is presented. The method is based on a path-integral decomposition and a worm operator which is local in imaginary time. It generates states with a fixed number of particles and respects other exact symmetries. Observables like the equal-time Green's function can be evaluated in an efficient way. To demonstrate the versatility of the method, results for the one-dimensional Bose-Hubbard model and a nuclear pairing model are presented. Within the context of the Bose-Hubbard model the efficiency of the algorithm is discussed.

Authors:
; ;  [1]
  1. Universiteit Gent, UGent, Vakgroep Subatomaire en Stralingsfysica, Proeftuinstraat 86, B-9000 Gent (Belgium)
Publication Date:
OSTI Identifier:
21069782
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 73; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevE.73.056703; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ALGORITHMS; COMPUTERIZED SIMULATION; EFFICIENCY; GREEN FUNCTION; HUBBARD MODEL; MONTE CARLO METHOD; NUCLEAR MODELS; ONE-DIMENSIONAL CALCULATIONS; PATH INTEGRALS; SUPERFLUIDITY; SYMMETRY

Citation Formats

Houcke, K. van, Rombouts, S. M. A., and Pollet, L.. Quantum Monte Carlo simulation in the canonical ensemble at finite temperature. United States: N. p., 2006. Web. doi:10.1103/PHYSREVE.73.056703.
Houcke, K. van, Rombouts, S. M. A., & Pollet, L.. Quantum Monte Carlo simulation in the canonical ensemble at finite temperature. United States. doi:10.1103/PHYSREVE.73.056703.
Houcke, K. van, Rombouts, S. M. A., and Pollet, L.. Mon . "Quantum Monte Carlo simulation in the canonical ensemble at finite temperature". United States. doi:10.1103/PHYSREVE.73.056703.
@article{osti_21069782,
title = {Quantum Monte Carlo simulation in the canonical ensemble at finite temperature},
author = {Houcke, K. van and Rombouts, S. M. A. and Pollet, L.},
abstractNote = {A quantum Monte Carlo method with a nonlocal update scheme is presented. The method is based on a path-integral decomposition and a worm operator which is local in imaginary time. It generates states with a fixed number of particles and respects other exact symmetries. Observables like the equal-time Green's function can be evaluated in an efficient way. To demonstrate the versatility of the method, results for the one-dimensional Bose-Hubbard model and a nuclear pairing model are presented. Within the context of the Bose-Hubbard model the efficiency of the algorithm is discussed.},
doi = {10.1103/PHYSREVE.73.056703},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 5,
volume = 73,
place = {United States},
year = {Mon May 15 00:00:00 EDT 2006},
month = {Mon May 15 00:00:00 EDT 2006}
}
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