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.
@article{arxiv.1202.1131,
title = {Atomic level micromagnetic model of recording media switching at elevated temperatures},
author = {J. I. Mercer and M. L. Plumer and J. P. Whitehead and anf J. van Ek},
journal= {arXiv preprint arXiv:1202.1131},
year = {2012}
}