Head and Granular Media for Thermally Assisted Magnetic Recording for Recording Density of 6 Tb/in $^{2}$

Optimum structural dimensions and characteristics of a granular thermally-assisted-magnetic-recording (TAMR) medium for a recording density of more than 6 Tb/in
²
were investigated by using optical, thermal, and Landau-Lifshitz-Gilbert (LLG) simulators. A sharp thermal profile in the medium could be obtained by using a heat-sink layer with heat conductivity greater than 100 W/m K. The ratio of in-plane κ to out-of-plane κ(κ
_xy
/κ
_g
) of the recording layer and thickness (Tm
_MgO
) of the MgO layer should both be decreased. The targets for magnetic-write width (MWW) and signal-to-noise ratio (SNR) are 18 nm and 12 dB for a recording density greater than 6 Tb/in
²
, respectively. In the case of Tm
_MgO
of 12 nm, the conditions for achieving these targets are ΔT of 450 K and H
_eff
of 1.36 MA/m. In the case of Tm
_MgO
of 5 nm, the conditions are ΔT of 600 K and H
_eff
of 1.4 MA/m (namely, MWW of 18 nm and recording density of 6.0 Tb/in
²
); ΔT of 550 K and H
_eff
of 1.48 MA/m (namely, MWW of 16.5 nm and recording density of 6.5 Tb/in
²
); and ΔT of 500 K and H
_eff
of 1.58 MA/m (namely, MWW of 15.0 nm and recording density of 7.2 Tb/in
²
). It is also clear that the thermal profile is a determinant factor in MWW.