Laminated antiferromagnetically coupled media for 100 Gb/In{sup}2 areal density and beyond

摘要

Experimental and micromagnetic simulation studies show that laminated antiferromagnetically coupled (LAC) media can push the areal density beyond 100 Gbit/in{sup}2. A technique is shown to obtain exchange-coupling constant as high as 0.32 erg/cm{sup}2, which is three-four times higher than the reported values in literature. This technique can improve the thermal stability factor by more than 40%. A new type of sandwich three-layer configuration for the antiferromagnetic coupled media is also proposed for the first time which may double the antiferromagnetic coupling effect for the recording CoCrPtB layer. It can also further reduce the Mrδ value (less than 0.2 memu/cm{sup}2) while keeping a high thermal stability that may be preferred for future applications, once extremely high-sensitive read heads appear in future. Micromagnetic simulation with 3D head field has been done for this kind of media. 200 Gbit/in{sup}2 areal density has been simulated using an orientation ratio of 2 for this kind of media.