Contribution of the magnetic anisotropy of the stabilization layer to the thermal stability of synthetic ferrimagnetic media

摘要

A study is reported on synthetic ferrimagnetic media, which is made of an initial or stabilization magnetic layer (L1) closer to the substrate and a thicker top magnetic layer (L2) separated by a Ru spacer layer. The effects of the magnetic anisotropy (K_(U-L1)) and the thickness (t_(L1)) of the stabilization layer on the thermal stability of synthetic ferrimagnetic media are systematically studied. The magnetic anisotropy K_(U-L1) is varied by changing the Pt content of CoCrPtB alloy while a constant thickness and the same composition are retained for the L2. Media coercivity, stabilization factor K_(U)V/k_(B)T, and thermal stability increase as a function of t_(L1). For a particular t_(L1) value, these factors are improved for higher K_(U-L1), though the interlayer antiferromagnetic coupling strength is decreased due to compositional changes.