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Stochastic series expansion method with operator-loop update

Anders W. Sandvik
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Abstract

A cluster update (the ``operator-loop'') is developed within the framework of a numerically exact quantum Monte Carlo method based on the power series expansion of exp(-BH) (stochastic series expansion). The method is generally applicable to a wide class of lattice Hamiltonians for which the expansion is positive definite. For some important models the operator-loop algorithm is more efficient than loop updates previously developed for ``worldline'' simulations. The method is here tested on a two-dimensional anisotropic Heisenberg antiferromagnet in a magnetic field.

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Anders W. Sandvik. 1999-02-16. Stochastic series expansion method with operator-loop update. https://doi.org/10.1103/physrevb.59.r14157

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