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arXiv · 0712.1290

Numerically exact Green functions from Hirsch-Fye quantum Monte Carlo simulations

N. Blümer
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Abstract

We present a new method for extracting numerically exact imaginary-time Green functions from standard Hirsch-Fye quantum Monte Carlo (HF-QMC) simulations within dynamical mean-field theory. By analytic continuation, angular resolved spectra are obtained without the discretization bias previously associated with HF-QMC results. The method is shown to be accurate even at very low temperatures (T=W/800 for bandwidth W) in the strongly correlated regime.

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N. Blümer. 2007-12-08. Numerically exact Green functions from Hirsch-Fye quantum Monte Carlo simulations. https://arxiv.org/abs/0712.1290

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