We revisit the accuracy of the variational Monte Carlo (VMC) method by taking an example of ground state properties for the one-dimensional Hubbard model. We start from the variational wave functions with the Gutzwiller and long-range Jastrow factor introduced by Capello et al. [Phys. Rev. B 72, 085121 (2005)] and further improve it by considering several quantum-number projections and a generalized one-body wave function. We find that the quantum spin projection and total momentum projection greatly improve the accuracy of the ground state energy within 0.5% error, for both small and large systems at half filling. Besides, the momentum distribution function n(k) at quarter filling calculated up to 196 sites allows us direct estimate of the critical exponents of the charge correlations from the power-law behavior of n(k) near the Fermi wave vector. Estimated critical exponents well reproduce those predicted by the Tomonaga-Luttinger theory.
|ジャーナル||Journal of Physics: Conference Series|
|出版ステータス||Published - 2013|
|イベント||24th IUPAP Conference on Computational Physics, IUPAP-CCP 2012 - Kobe, Japan|
継続期間: 2012 10 14 → 2012 10 18
ASJC Scopus subject areas
- Physics and Astronomy(all)