A perpendicular magnetic recording system and medium has a multilayered
recording layer that includes an exchange-spring structure and a
ferromagnetic lateral coupling layer (LCL). The exchange-spring structure
is made up of two ferromagnetically exchange-coupled magnetic layers
(MAG1 and MAG2), each with perpendicular magnetic anisotropy. MAG1 and
MAG2 may have a coupling layer (CL) located between them that permits
ferromagnetic exchange coupling of MAG1 with MAG2. The LCL is located
either above or below MAG1 and in direct contact with MAG1 and mediates
an effective intergranular exchange coupling in MAG1. The ferromagnetic
alloy in the LCL has significantly greater intergranular exchange
coupling than the ferromagnetic alloy in MAG1, which typically will
include segregants such as oxides. The LCL is preferably free of oxides
or other non-metallic segregants, which would tend to reduce
intergranular exchange coupling in the LCL. Because the LCL grain
boundaries overlay the boundaries of the generally segregated and
decoupled grains of MAG1, and the LCL and MAG1 grains are strongly
coupled perpendicularly, the LCL introduces an effective intergranular
exchange coupling in the MAG1.