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Proximity effects in spin-triplet superconductor-ferromagnet heterostucture with spin-active interface

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 نشر من قبل Damien Terrade
 تاريخ النشر 2012
  مجال البحث فيزياء
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We study the physical properties of a ballistic heterostructure made of a ferromagnet (FM) and a spin-triplet superconductor (TSC) with a layered structure stacking along the direction perpendicular to the planes where a chiral px+ipy pairing occurs and assuming spin dependent processes at the interface. We use a self-consistent Bogoliubov-de Gennes approach on a three-dimensional lattice to obtain the spatial profiles of the pairing amplitude and the magnetization. We find that, depending on the strength of the ferromagnetic exchange field, the ground state of the system can have two distinct configurations with a parallel or anti-parallel collinearity between the magnetic moments in the bulk and at the interface. We demonstrate that a magnetic state having non coplanar interface, bulk and Cooper pairs spins may be stabilized if the bulk magnetization is assumed to be fixed along a given direction. The study of the density of states reveals that the modification of the electronic spectrum in the FM plays an important role in the setting of the optimal magnetic configuration. Finally, we find the existence of induced spin-polarized pair correlations in the FM-TSC system.



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