Lateral Exchange Spring Media

One of the main challenges in magnetic recording is to obtain a sufficient high thermal stability and at the same time a good writeability of the media. Recently, composite media and exchange spring media were proposed in order to shift the problem of writeability to higher areal densities. A similar concept can be applied to a recently proposed recording media called percolation media. In this paper, finite element micromagnetic simulations were done for a lateral exchange spring percolation media. It is concluded that percolation media require a sufficient high value of magnetic anisotropy constant K₁ so that the thermal stability is high enough and the domain wall width is sufficiently small to allow for high signal to noise ratios. It is shown that on such hard magnetic media bits can be written by the introduction of a soft magnetic track.