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Direct observation of the superconducting gap in phonon spectra

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 نشر من قبل Frank Weber
 تاريخ النشر 2008
  مجال البحث فيزياء
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We show that the superconducting energy gap $Delta$ can be directly observed in phonon spectra, as predicted by recent theories. In addition, since each phonon probes the gap on only a small part of the Fermi surface, the gap anisotropy can be studied in detail. Our neutron scattering investigation of the anisotropic conventional superconductor YNi$_2$B$_2$C demonstrates this new application of phonon spectroscopy.



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