Write field calculation for a narrow-track, single-pole head with a thin underlayer of perpendicular medium

The recording field of a narrow-track, single-pole (SPT) write head with a double-layered medium was investigated using three-dimensional eddy current transient finite element analysis. In the calculations, a soft-magnetic underlayer with a thickness of 100 nm was assumed. The results illustrate a large head field strength at a track width of 100 nm and a large recording field gradient at the trailing edge.