Nonlinear transition shift measurement in perpendicular magnetic recording

Transition-shift distortion for perpendicular magnetic recording is measured using a pseudorandom sequence and extracted dipulse analysis. The analysis reveals moderately low distortion at a high linear density of 318 kFRPI. Perpendicular recording is expected to give rise to transition-shift distortion in a direction opposite to that for longitudinal recording. However, very little transition-shift distortion is observed. The distortion that does occur appears to be predominantly a narrowing of 'following' transitions.