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Spectral Functions of One-dimensional Models of Correlated Electrons

Julien Favand·Stephan Haas·Karlo Penc·Frederic Mila·Elbio Dagotto
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Abstract

Using the Ogata-Shiba wave function, the spectral functions of the one-dimensional infinite U Hubbard model are calculated for various concentrations. It is shown that the ``shadow band'' feature due to 2k_F fluctuations becomes more intense close to half-filling. Comparing these results with exact diagonalization data obtained on finite clusters for the finite U Hubbard model and for the t-J model, it is also shown that this feature remains well-defined for physically reasonable values of the parameters (U/t\simeq 10, J/t\simeq 0.4). The ``shadow'' structure in the spectral functions should thus be observable in angle-resolved photoemission experiments for a variety of quasi-one dimensional compounds.

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Julien Favand, Stephan Haas, Karlo Penc, Frederic Mila, Elbio Dagotto. 1996-11-27. Spectral Functions of One-dimensional Models of Correlated Electrons. https://doi.org/10.1103/physrevb.55.r4859

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