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Superconductivity Driven by Chain Coupling and Electronic Correlations

J. M. P. Carmelo·F. Guinea·K. Penc·P. D. Sacramento
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Abstract

We present an analysis of a system of weakly coupled Hubbard chains based on combining an exact study of spectral functions of the uncoupled chain system with a renormalization group method for the coupled chains. For low values of the onsite repulsion $U$ and of the doping $δ$, the leading instability is towards a superconducting state. The process includes excited states above a small correlation pseudogap. Similar features appear in extended Hubbard models in the vicinity of commensurate fillings. Our theoretical predictions are consistent with the phase diagram observed in the (TMTTF)$_2$X and (TMTSF)$_2$X series of organic compounds.

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J. M. P. Carmelo, F. Guinea, K. Penc, P. D. Sacramento. 2004-05-21. Superconductivity Driven by Chain Coupling and Electronic Correlations. https://doi.org/10.1209/epl%2Fi2004-10273-7

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