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Correlations in a two--chain Hubbard model

R. M. Noack·S. R. White·D. J. Scalapino
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Abstract

Equal time spin--spin and pair field correlation functions are calculated for a two-chain Hubbard model using a density-matrix numerical renormalization group approach. At half-filling, the antiferromagnetic and pair field correlations both decay exponentially with the pair field having a much shorter correlation length. This is consistent with a gapped spin-liquid ground state. Below half--filling, the antiferromagnetic correlations become incommensurate and the spin gap persists. The pair field correlations appear to follow a power law decay which is similar to their non-interacting U=0 behavior.

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R. M. Noack, S. R. White, D. J. Scalapino. 1994-03-08. Correlations in a two--chain Hubbard model. https://doi.org/10.1103/physrevlett.73.882

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