Multiscale modeling of ultrafast element-specific magnetization dynamics in FeNi ferromagnetic alloys

  title={Multiscale modeling of ultrafast element-specific magnetization dynamics in FeNi ferromagnetic alloys},
  author={Denise Hinzke and Unai Atxitia and Karel Carva and Pablo Nieves and Oksana Chubykalo-Fesenko and Peter M. Oppeneer and Ulrich Nowak},
  journal={2015 IEEE Magnetics Conference (INTERMAG)},
Herein, to understand the differences of the magnetization dynamics of Fe and Ni in Py, we develop a model based on a hierarchical multi-scale approach to investigate the sub-lattice dynamics of ferromagnetic alloys and to obtain a deeper insight into the underlying mechanisms. First, we construct and parametrize a spin model Hamiltonian for Py on the basis of first-principles calculations. This spin model Hamiltonian in combination with extensive atomistic spin computer simulations based on… 

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