Narrow Track Confinement by AC Field Generation Layer in Microwave Assisted Magnetic Recording

Microwave assisted magnetic recording (MAMR) has been proposed to provide sufficient writability in magnetic recording when the magnetic grain has a large crystalline anisotropy field in high recording density. In this paper, the relationship between the track width and recording head designs in this novel recording scheme is studied using micromagnetic modeling. By controlling the AC field generation layer width, high track density can be obtained without decreasing the main pole width in the writer. A quantitive result shows 770 KTPI can be realized in MAMR with a 120 nm wide main pole and 25 nm wide AC field generation layer.