Patterned perpendicular magnetic recording disk drive and medium with patterned exchange bridge layer below the data islands

A patterned perpendicular magnetic recording disk comprising:

• a substrate;
• a soft underlayer (SUL) of soft magnetically permeable material on the substrate;
• a nonmagnetic exchange break layer (EBL) on the SUL;
• an exchange bridge layer of soft magnetically permeable material on the EBL, the exchange bridge layer comprising a base layer and a plurality of pedestals extending from the base layer and arranged in a pattern of generally concentric data tracks;
• a coupling control layer (CCL) on each pedestal and selected from a nonmagnetic material and a weakly ferromagnetic material;
• and
• a magnetic data island comprising perpendicular magnetic recording material on the CCL of each pedestal, the perpendicular magnetic recording material having a saturation magnetic flux density less than the saturation magnetic flux density of the exchange bridge material, wherein adjacent data islands and their underlying CCLs are connected by the exchange bridge layer, the CCL on each pedestal providing ferromagnetic exchange coupling between the perpendicular magnetic recording material above it and the exchange bridge material below it, and the exchange bridge layer and CCLs controlling exchange interaction between adjacent data islands to compensate for dipolar fields between adjacent islands.