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Violation of Luttinger's Theorem in the Two-Dimensional t-J Model

W. O. Putikka·M. U. Luchini·R. R. P. Singh
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Abstract

We have calculated the high temperature series for the momentum distribution function n_k of the 2D t-J model to 12th order in inverse temperature. By extrapolating the series to T=0.2J we searched for a Fermi surface of the 2D t-J model. We find that three criteria used for estimating the location of a Fermi surface violate Luttinger's Theorem, implying the 2D t-J model does not have an adiabatic connection to a non-interacting model.

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W. O. Putikka, M. U. Luchini, R. R. P. Singh. 1998-03-11. Violation of Luttinger's Theorem in the Two-Dimensional t-J Model. https://doi.org/10.1103/physrevlett.81.2966

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