Effect of Curie Temperature Distributions on the User Areal Density of Heat-Assisted Magnetic Recording

The effect of Curie temperature distributions and average grain size on the user areal density (UAD) of heat-assisted magnetic recording media was calculated for target areal densities of 2, 3 and 4 Tbit/in
²
. A grain switching probability model was used to write tracks and the bit error rate evaluated, allowing the UAD to be calculated. A 10% Curie temperature distribution reduced the UAD by 0.5 - 0.8 Tbit/in
²
, with larger reductions for media with smaller grains. The effect of the reader on the UAD was also evaluated and found to be less significant for media with
T_c
distributions.