Abstract
We introduce a method that combines the power of both the lattice Green' function Monte Carlo (LGFMC) with the auxiliary field quantum Monte Carlo (AFQMC) techniques, and allows us to compute exact ground-state properties of the Hubbard model for on finite clusters. Thanks to LGFMC, one obtains unbiased zero temperature results, not affected by the so-called Trotter approximation of the imaginary time propagator . At the same time, the AFQMC formalism yields a remarkably fast convergence in before the fermion sign problem becomes prohibitive. As an application we report ground-state energies of the Hubbard model at with up to 100 sites.
- Received 3 October 2011
DOI:https://doi.org/10.1103/PhysRevB.84.241110
©2011 American Physical Society