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Quantitative simulation of temperature dependent magnetization dynamics and equilibrium properties of elemental ferromagnets

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 نشر من قبل Richard Evans
 تاريخ النشر 2014
  مجال البحث فيزياء
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Atomistic spin model simulations are immensely useful in determining temperature dependent magnetic prop- erties, but are known to give the incorrect dependence of the magnetization on temperature compared to exper- iment owing to their classical origin. We find a single parameter rescaling of thermal fluctuations which gives quantitative agreement of the temperature dependent magnetization between atomistic simulations and experi- ment for the elemental ferromagnets Ni, Fe, Co and Gd. Simulating the sub-picosecond magnetization dynam- ics of Ni under the action of a laser pulse we also find quantitative agreement with experiment in the ultrafast regime. This enables the quantitative determination of temperature dependent magnetic properties allowing for accurate simulations of magnetic materials at all temperatures.



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