Time-resolved spin-torque switching and enhanced damping in permalloy/Cu/permalloy spin-valve nanopillars.

نویسندگان

  • N C Emley
  • I N Krivorotov
  • O Ozatay
  • A G F Garcia
  • J C Sankey
  • D C Ralph
  • R A Buhrman
چکیده

We report time-resolved measurements of current-induced reversal of a free magnetic layer in Permalloy/Cu/Permalloy elliptical nanopillars at temperatures T=4.2 K to 160 K. Comparison of the data to Landau-Lifshitz-Gilbert macrospin simulations of the free layer switching yields numerical values for the spin torque and the Gilbert damping parameters as functions of T. The damping is strongly T dependent, which we attribute to the presence of an antiferromagnetic oxide layer around the perimeter of the Permalloy free layer. This adventitious antiferromagnetic oxide can have a major impact on spin-torque phenomena.

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عنوان ژورنال:
  • Physical review letters

دوره 96 24  شماره 

صفحات  -

تاریخ انتشار 2006