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General spectral function expressions of a 1D correlated model

J. M. P. Carmelo·K. Penc
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Abstract

We introduce a method that allows the evaluation of general expressions for the spectral functions of the one-dimensional Hubbard model for all values of the on-site electronic repulsion U. The spectral weights are expressed in terms of pseudofermion operators such that the spectral functions can be written as a convolution of pseudofermion dynamical correlation functions. Our results are valid for all finite energy and momentum values and are used elsewhere in the study of the unusual finite-energy properties of quasi-one-dimensional compounds and the new quantum systems of ultra-cold fermionic atoms on an optical lattice.

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J. M. P. Carmelo, K. Penc. 2005-12-20. General spectral function expressions of a 1D correlated model. https://arxiv.org/abs/cond-mat/0311075

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