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High domain wall velocity at zero magnetic field induced by low current densities in spin-valve nanostripes

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 نشر من قبل Jan Vogel
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Stefania Pizzini




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Current-induced magnetic domain wall motion at zero magnetic field is observed in the permalloy layer of a spin-valve-based nanostripe using photoemission electron microscopy. The domain wall movement is hampered by pinning sites, but in between them high domain wall velocities (exceeding 150 m/s) are obtained for current densities well below $10^{12} unit{A/m^2}$, suggesting that these trilayer systems are promising for applications in domain wall devices in case of well controlled pinning positions. Vertical spin currents in these structures provide a potential explanation for the increase in domain wall velocity at low current densities.



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