Micromagnetics of Percolated Perpendicular Media for 1 Tbits/in2 and beyond

This paper presents detailed micromagnetic analysis of the magnetization reversal characteristics and recording properties and comparison with the conventional granular perpendicular media (GPM) will be discussed. The percolated perpendicular media (PPM) consists of exchange coupled magnetic grains with strong perpendicular anisotropy and, more or less uniformly and relatively densely distributed small non-magnetic grains, acting as domain wall pinning sites. For the PPM, the pinning sites are assumed to be 2 nm in diameter while for GPM, the grain size is assumed to be 8nm with zero intergranular exchange coupling. The PPM shows significantly shaper transition profile than that of the GPM due to the fact that densely distributed pinning sites yields much smoother transition boundaries.