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Stochastic gradient approximation method applied to Hubbard model

A. Harju
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Abstract

The two-dimensional Hubbard model is studied using the variational quantum Monte Carlo technique with Gutzwiller-type variational wave functions. In addition to the simple one-site correlated Gutzwiller wave function, we use a form with correlation between electrons on nearest- and next-nearest-neighbor sites. We show that the stochastic gradient approximation method suits very well for the optimization of the free parameters of the variational wave functions.

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A. Harju. 2001-01-31. Stochastic gradient approximation method applied to Hubbard model. https://arxiv.org/abs/cond-mat/0101465

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