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Phonon and Magnetic Pairing Mechanisms in High-Temperature Superconductors in the Strong Correlation Mode

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 نشر من قبل Elena Shneyder I.
 تاريخ النشر 2007
  مجال البحث فيزياء
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The t-t-t-J model of electrons interacting with three phonon modes (breathing, apical breathing, and buckling) is considered. The wave-vector dependence of the matrix elements of the electron-phonon interaction leads to opposite contributions to the pairing potential with the d-symmetry: the buckling mode facilitates electron pairing, while the breathing mode suppresses it. As a result, the critical temperature of La{2 - x}Sr{x}CuO{4} that is associated with the magnetic mechanism is lowered when phonons are taken into account.



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