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arXiv · 1504.05090

Deciding the fate of the false Mott transition in two dimensions by exact quantum Monte Carlo methods

D. Rost·N. Blümer
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Abstract

We present an algorithm for the computation of unbiased Green functions and self-energies for quantum lattice models, free from systematic errors and valid in the thermodynamic limit. The method combines direct lattice simulations using the Blankenbecler Scalapino-Sugar quantum Monte Carlo (BSS-QMC) approach with controlled multigrid extrapolation techniques. We show that the half-filled Hubbard model is insulating at low temperatures even in the weak-coupling regime; the previously claimed Mott transition at intermediate coupling does not exist.

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D. Rost, N. Blümer. 2015-04-20. Deciding the fate of the false Mott transition in two dimensions by exact quantum Monte Carlo methods. https://doi.org/10.1088/1742-6596/640/1/012047

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