2009/05/31 by F Mezzacapo, Fabio Mezzacapo, N Schuch +5 · 2 citations
Computer Science · Mathematics · Physics and Astronomy · #Algebraic structures and combinatorial models #Ansatz #Cover (algebra) #Function (biology) #Lattice (music) #Monte Carlo method #Quantum #Quantum Computing Algorithms and Architecture #Quantum Monte Carlo #Quantum many-body systems #Variational Monte Carlo #Wave function #cond-mat.str-el
paper · pdf · doi:10.1088/1367-2630/11/8/083026
published as New J. Phys. 11 (2009) 083026 · 5 pages, 2 figures (see also arXiv:0907.4646)
openalex publication_date 2009/08/24 · arxiv created 2009/08/26 · arxiv updated 2015/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We propose a new ansatz for the ground-state wave function of quantum many-body systems on a lattice. The key idea is to cover the lattice with plaquettes and obtain a state whose configurational weights can be optimized by means of a variational Monte Carlo algorithm. Such a scheme applies to any dimension, without any 'sign' instability. We show results for various two-dimensional spin models (including frustrated ones). A detailed comparison with available exact results, as well as with variational methods based on different ansatze, is offered. In particular, our numerical estimates are in quite good agreement with exact ones for unfrustrated systems, and compare favorably to other methods for frustrated ones.