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The Mott insulator - 10th order perturbation theory extended to infinite order using QMC

N. Blümer·E. Kalinowski
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Abstract

We present a new method, based on the combination of analytical and numerical techniques within the framework of the dynamical mean-field theory (DMFT). Building upon numerically exact results obtained in an improved quantum Monte Carlo (QMC) scheme, 10th order strong-coupling perturbation theory for the Hubbard model on the Bethe lattice is extrapolated to infinite order. We obtain continuous estimates of energy E and double occupancy D with unprecedented precision O(10^{-5}) for the Mott insulator above its stability edge U_{c1}=4.78 as well as critical exponents. The relevance for recent experiments on Cr-doped V_2O_3 is pointed out.

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N. Blümer, E. Kalinowski. 2004-12-03. The Mott insulator - 10th order perturbation theory extended to infinite order using QMC. https://doi.org/10.1103/physrevb.71.195102

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