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

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 نشر من قبل Marcello Civelli
 تاريخ النشر 2009
  مجال البحث فيزياء
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 تأليف M. Civelli




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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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