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Magnetic switching dynamics in a ferrimagnetic two sub-lattice model including ultrafast exchange scattering

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 نشر من قبل Hans Christian Schneider
 تاريخ النشر 2014
  مجال البحث فيزياء
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We study the heat-induced magnetization dynamics in a toy model of a ferrimagnetic alloy, which includes localized spins antiferromagnetically coupled to an itinerant carrier system with a Stoner gap. We determine the one-particle spin-density matrix including exchange scattering between localized and itinerant bands as well as scattering with phonons. While a transient ferromagnetic-like state can always be achieved by a sufficiently strong excitation, this transient ferromagnetic-like state only leads to magnetization switching for model parameters that also yield a compensation point in the equilibrium M(T) curve.



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