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arXiv · 1002.1671

Threshold Singularities in the One Dimensional Hubbard Model

F. H. L. Essler
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Abstract

We consider excitations with the quantum numbers of a hole in the one dimensional Hubbard model below half-filling. We calculate the finite-size corrections to the energy. The results are then used to determine threshold singularities in the single-particle Green's function for commensurate fillings. We present the analogous results for the Yang-Gaudin model (electron gas with delta-function interactions).

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F. H. L. Essler. 2010-02-08. Threshold Singularities in the One Dimensional Hubbard Model. https://doi.org/10.1103/physrevb.81.205120

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