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arXiv · 1606.01874

Switching field distribution of exchange coupled ferri-/ferromagnetic composite bit patterned media

Harald Oezelt·Alexander Kovacs·Johann Fischbacher·Patrick Matthes·Eugenie Kirk·Phillip Wohlhüter·Laura Jane Heyderman·Manfred Albrecht·Thomas Schrefl
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Abstract

We investigate the switching field distribution and the resulting bit error rate of exchange coupled ferri-/ferromagnetic bilayer island arrays by micromagnetic simulations. Using islands with varying microstructure and anisotropic properties, the intrinsic switching field distribution is computed. The dipolar contribution to the switching field distribution is obtained separately by using a model of a triangular patterned island array resembling $1.4\,\mathrm{Tb/in}^2$ bit patterned media. Both contributions are computed for different thickness of the soft exchange coupled ferrimagnet and also for ferromagnetic single phase FePt islands. A bit patterned media with a bilayer structure of FeGd($5\,\mathrm{nm}$)/FePt($5\,\mathrm{nm}$) shows a bit error rate of $10^{-4}$ with a write field of $1.16\,\mathrm{T}$.

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Harald Oezelt, Alexander Kovacs, Johann Fischbacher, Patrick Matthes, Eugenie Kirk, Phillip Wohlhüter, Laura Jane Heyderman, Manfred Albrecht, Thomas Schrefl. 2016-09-02. Switching field distribution of exchange coupled ferri-/ferromagnetic composite bit patterned media. https://doi.org/10.1063/1.4962213

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