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Current Induced Fingering Instability in Magnetic Domain Walls

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 نشر من قبل Jon Gorchon Dr
 تاريخ النشر 2014
  مجال البحث فيزياء
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The shape instability of magnetic domain walls under current is investigated in a ferromagnetic (Ga,Mn)(As,P) film with perpendicular anisotropy. Domain wall motion is driven by the spin transfer torque mechanism. A current density gradient is found either to stabilize domains with walls perpendicular to current lines or to produce finger-like patterns, depending on the domain wall motion direction. The instability mechanism is shown to result from the non-adiabatic contribution of the spin transfer torque mechanism.



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