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Memory Effect in the Photoinduced Femtosecond Rotation of Magnetization in the Ferromagnetic Semiconductor GaMnAs

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 نشر من قبل Jigang Wang
 تاريخ النشر 2008
  مجال البحث فيزياء
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We report a femtosecond response in photoinduced magnetization rotation in the ferromagnetic semiconductor GaMnAs, which allows for detection of a four-state magnetic memory at the femtosecond time scale. The temporal profile of this cooperative magnetization rotation exhibits a discontinuity that reveals two distinct temporal regimes, marked by the transition from a highly non-equilibrium, carrier-mediated regime within the first 200 fs, to a thermal, lattice-heating picosecond regime.



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