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The Dimer Model for k-phase Organic Superconductors

G. Visentini·A. Painelli·A. Girlando·A. Fortunelli
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Abstract

We prove that the upper electronic bands of k-phase BEDT-TTF salts are adequately modeled by an half-filled tight-binding lattice with one site per cell. The band parameters are derived from recent ab-initio calculations, getting a very simple but extremely accurate one-electron picture. This picture allows us to solve the BCS gap equation adopting a real-space pairing potential. Comparison of the calculated superconducting properties with the experimental data points to isotropic s_0-pairing. Residual many-body or phonon-mediated interactions offer a plausible explanation of the large variety of physical properties observed in k-phase BEDT-TTF salts.

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G. Visentini, A. Painelli, A. Girlando, A. Fortunelli. 1997-06-02. The Dimer Model for k-phase Organic Superconductors. https://doi.org/10.1209/epl%2Fi1998-00273-1

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