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Strongly Correlated Superconductivity and Pseudogap Phase near a multi-band Mott Insulator

M. Capone·M. Fabrizio·C. Castellani·E. Tosatti
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Abstract

Near a Mott transition, strong electron correlations may enhance Cooper pairing. This is demonstrated in the Dynamical Mean Field Theory solution of a twofold-orbital degenerate Hubbard model with inverted Hund's rules on-site exchange, which favors local spin-singlet configurations. Close to the Mott insulator, which is a local version of a valence bond insulator, a pseudogap non-Fermi-liquid metal, a superconductor, and a normal metal appear, in striking similarity with the physics of the cuprates. The strongly correlated superconducting state has a larger Drude weight than the corresponding normal state. The role of the impurity Kondo problem is underscored.

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M. Capone, M. Fabrizio, C. Castellani, E. Tosatti. 2004-07-22. Strongly Correlated Superconductivity and Pseudogap Phase near a multi-band Mott Insulator. https://doi.org/10.1103/physrevlett.93.047001

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