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Theory for Gossamer and Resonating Valence Bond Superconductivity

J. Y. Gan·F. C. Zhang·Z. B. Su
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Abstract

We use an effective Hamiltonian for two-dimensional Hubbard model including an antiferromagnetic spin-spin coupling term to study recently proposed gossamer superconductivity. We formulate a renormalized mean field theory to approximately take into account the strong correlation effect in the partially projected Gutzwiller wavefucntions. At the half filled, there is a first order phase transition to separate a Mott insulator at large Coulomb repulsion U from a gossamer superconductor at small U. Away from the half filled,the Mott insulator is evolved into an resonating valence bond state, which is adiabatically connected to the gossamer superconductor.

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J. Y. Gan, F. C. Zhang, Z. B. Su. 2003-08-20. Theory for Gossamer and Resonating Valence Bond Superconductivity. https://doi.org/10.1103/physrevb.71.014508

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