Patent ID: 7862912

Claim:
A perpendicular magnetic recording medium comprising: a substrate; a first ferromagnetic layer (PM 1 ) on the substrate and having perpendicular magnetic anisotropy; a second ferromagnetic layer (PM 2 ) on the substrate and having perpendicular magnetic anisotropy; an antiferromagnetically coupling (AFC) layer between PM 1 and PM 2 ; and a ferromagnetic switching layer (SWL) between PM 1 and PM 2 and having a Curie temperature (T C-SWL ) less than the Curie temperature (T C-PM1 ) of PM 1 and less than the Curie temperature (T C-PM2 ) of PM 2 , the SWL comprising a plurality of pairs of alternating films of a first film consisting essentially of Co and Ni and a second film selected from Pt and Pd.