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Tracing the thermal mechanism in femtosecond spin dynamics

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 نشر من قبل Oksana Chubykalo-Fesenko
 تاريخ النشر 2009
  مجال البحث فيزياء
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We compare femtosecond pump-probe experiments in Ni and micromagnetic modelling based on the Landau-Lifshitz-Bloch equation coupled to a two-temperature model, revealing a predominant thermal ultrafast demagnetization mechanism. We show that both spin (femtosecond demagnetization) and electron-phonon (magnetization recovery) rates in Ni increase as a function of the laser pump fluence. The slowing down for high fluences arises from the increased longitudinal relaxation time.



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