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Diffusion Monte Carlo with lattice regularization

Michele Casula·Claudia Filippi·Sandro Sorella
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Abstract

We introduce an efficient lattice regularization scheme for quantum Monte Carlo calculations of realistic electronic systems. The kinetic term is discretized by a finite difference Laplacian with two mesh sizes, a and a', where a'/a is an irrational number so that the electronic coordinates are not defined on a particular lattice but on the continuous configuration space. The regularized Hamiltonian goes to the continuous limit for a -> 0 and provides several advantages. In particular, it allows the inclusion of non-local potentials in a consistent variational scheme, substantially improving the accuracy upon previous non-variational approaches.

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Michele Casula, Claudia Filippi, Sandro Sorella. 2005-02-16. Diffusion Monte Carlo with lattice regularization. https://doi.org/10.1103/physrevlett.95.100201

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