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arXiv · 0812.1201

Evolution of the dynamical pairing across the phase diagram of a strongly correlated high-temperature superconductor

M. Civelli
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Abstract

We study the dynamics of the Cooper pairing across the T=0 phase diagram of the two-dimensional Hubbard Model, relevant for high-temperature superconductors, using a cluster extension of dynamical mean field theory. We find that the superconducting pairing function evolves from an unconventional form in the over-doped region into a more conventional boson-mediated retarded form in the under-doped region of the phase diagram. The boson, however, promotes the rise of a pseudo-gap in the electron density of states rather than a superconducting gap as in the standard theory of superconductivity. We discuss our results in terms of Mott-related phenomena, and we show that they can be observed in tunneling experiments.

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M. Civelli. 2009-09-24. Evolution of the dynamical pairing across the phase diagram of a strongly correlated high-temperature superconductor. https://doi.org/10.1103/physrevlett.103.136402

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