Observation of magnetic interaction between the soft magnetic and the recording layers in double-layer perpendicular media

Magnetic force microscopy was used to study the magnetic interaction in double-layer perpendicular media between the CoCrPt recording layer and the CoTaZr soft magnetic layer by observing the magnetization structure from the soft magnetic layer side. A strong magnetic interaction between the two layers was observed when the layers were in direct contact. Introducing a thin nonmagnetic layer between the two magnetic layers reduced the magnetic interaction and resulted in the reduction of the media noise of double-layer perpendicular media.