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Penetration of Andreev bound states into the ferromagnet in a SrRuO$_{3}$/(110)YBa$_2$Cu$_3$O$_{7-delta}$ bilayer: a scanning tunneling spectroscopy study

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 نشر من قبل Itay Asulin
 تاريخ النشر 2007
  مجال البحث فيزياء
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Scanning tunneling spectroscopy of thin epitaxial $SrRuO_{3}/(110)YBa_2Cu_3O_{7-delta}$ ferromagnet/superconductor bilayers, reveal a clear penetration of the Andreev bound states into the ferromagnetic layer. The penetration is manifested in the density of states of the ferromagnet as a split zero bias conductance peak with an imbalance between peak heights. Our data indicate that the splitting occurs at the superconductor side as a consequence of induced magnetization, confirming recent theoretical predictions. The imbalance is attributed to the spin polarization in the ferromagnet.



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