High-density perpendicular recording media with large grain separation

The possibility of 300-500 Gbit/in² perpendicular recording using granular recording media has been investigated through micromagnetic simulation based on the Langevin equation. Writability and thermal stability in 10 years were obtained changing media parameters such as the grain size D, the grain separation d, and the thickness of the recording layer t_mag for proper combination of the grain saturation magnetization M_s-grain and the grain perpendicular anisotropy energy K_u-grain. It was found that high-density recording is realized under the large grain separation, the large grain saturation magnetization, and the large grain anisotropy energy. The read/write calculation using ordered medium with D of 4.2 nm, d of 2.3 nm, t_mag of 12.0 nm, M_s-grain of 1313 emu/cm³, and K_u-grain of 7.0 Merg/cm³ confirmed the possibility of 1303 kFCI and 1954 kFCI perpendicular recording, leading to 325 and 488 Gbit/in² with 250 kTPI (track pitch of 102 nm).