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arXiv · 1902.00322

Diagonal Padé Approximant of the one-body Green's function, a study on Hubbard rings

Walter Tarantino·Stefano Di Sabatino
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Abstract

Padé approximants to the many-body Green's function can be built by rearranging terms of its perturbative expansion. The hypothesis that the best use of a finite number of terms of such an expansion is given by the subclass of diagonal Padé approximants is here tested, and largely confirmed, on a solvable model system, namely the Hubbard ring for a variety of site numbers, fillings and interaction strengths.

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Walter Tarantino, Stefano Di Sabatino. 2019-02-01. Diagonal Padé Approximant of the one-body Green's function, a study on Hubbard rings. https://doi.org/10.1103/physrevb.99.075149

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