A field-theoretical approach to the extended Hubbard model

Z. Koinov

doi:10.1016/j.physc.2009.11.140

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arXiv · 1002.0254

A field-theoretical approach to the extended Hubbard model

Z. Koinov

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Abstract

We transform the quartic Hubbard terms in the extended Hubbard model to a quadratic form by making the Hubbard-Stratonovich transformation for the electron operators. This transformation allows us to derive exact results for mass operator and charge-charge and spin-spin correlation functions for s-wave superconductivity. We discuss the application of the method to the d-wave superconductivity.

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Z. Koinov. 2010-02-01. A field-theoretical approach to the extended Hubbard model. https://doi.org/10.1016/j.physc.2009.11.140

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