Atomic level micromagnetic model of recording media switching at elevated temperatures

J. I. Mercer; M. L. Plumer; J. P. Whitehead; anf J. van Ek

doi:10.1063/1.3589968

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arXiv · 1202.1131

Atomic level micromagnetic model of recording media switching at elevated temperatures

J. I. Mercer·M. L. Plumer·J. P. Whitehead·anf J. van Ek

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Abstract

An atomic level micromagnetic model of granular recording media is developed and applied to examine external field-induced grain switching at elevated temperatures which captures non-uniform reversal modes. The results are compared with traditional methods which employ the Landau-Lifshitz-Gilbert equations based on uniformly magnetized grains with assigned intrinsic temperature profiles for $M(T)$ and $K(T)$. Using nominal parameters corresponding to high-anisotropy FePt-type media envisioned for Energy Assisted Magnetic Recording, our results demonstrate that atomic-level reversal slightly reduces the field required to switch grains at elevated temperatures, but results in larger fluctuations, when compared to a uniformly magnetized grain model.

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J. I. Mercer, M. L. Plumer, J. P. Whitehead, anf J. van Ek. 2012-02-06. Atomic level micromagnetic model of recording media switching at elevated temperatures. https://doi.org/10.1063/1.3589968

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