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Continuous Time Quantum Monte Carlo method for fermions

A. N. Rubtsov·V. V. Savkin·A. I. Lichtenstein
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Abstract

We present numerically exact continuous-time Quantum Monte Carlo algorithm for fermions with a general non-local in space-time interaction. The new determinantal grand-canonical scheme is based on a stochastic series expansion for the partition function in the interaction representation. The method is particularly applicable for multi-band time-dependent correlations since it does not invoke the Hubbard-Stratonovich transformation. The test calculations for exactly solvable models as well results for the Green function and for the time-dependent susceptibility of the multi-band super-symmetric model with a spin-flip interaction are discussed.

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A. N. Rubtsov, V. V. Savkin, A. I. Lichtenstein. 2005-03-07. Continuous Time Quantum Monte Carlo method for fermions. https://doi.org/10.1103/physrevb.72.035122

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