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A Constrained Path Quantum Monte Carlo Method for Fermion Ground States

Shiwei Zhang·J. Carlson·J. E. Gubernatis
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Abstract

We propose a new quantum Monte Carlo algorithm to compute fermion ground-state properties. The ground state is projected from an initial wavefunction by a branching random walk in an over-complete basis space of Slater determinants. By constraining the determinants according to a trial wavefunction $|Ψ_T \rangle$, we remove the exponential decay of signal-to-noise ratio characteristic of the sign problem. The method is variational and is exact if $|Ψ_T\rangle$ is exact. We report results on the two-dimensional Hubbard model up to size $16\times 16$, for various electron fillings and interaction strengths.

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Shiwei Zhang, J. Carlson, J. E. Gubernatis. 1995-03-10. A Constrained Path Quantum Monte Carlo Method for Fermion Ground States. https://doi.org/10.1103/physrevlett.74.3652

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