Pseudogap in cuprate and organic superconductors

J. Merino; O. Gunnarsson

doi:10.1016/j.physc.2012.10.009

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arXiv · 1208.3996

Pseudogap in cuprate and organic superconductors

J. Merino·O. Gunnarsson

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Abstract

We study the pseudogap present in cuprate and organic superconductors. We use the dynamical cluster approximation (DCA), treating a cluster embedded in a bath. As the Coulomb interaction is increased, cluster-bath Kondo states are destroyed and bound cluster states formed. We show that this leads to a pseudogap. Due to weaker coupling to the bath for the anti-nodal point, this happens first for this point, explaining the k-dependence of the pseudogap. The pseudogap can be understood in terms of preformed d-wave pairs, but it does not prove the existence of such pairs.

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J. Merino, O. Gunnarsson. 2012-08-20. Pseudogap in cuprate and organic superconductors. https://doi.org/10.1016/j.physc.2012.10.009

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