Media saturation and overwrite in perpendicular recording

A novel spin-stand method for measuring the perpendicular write pole "footprint" is proposed. This method allows the detailed study of the spatio-temporal pole footprint dynamics and the two-dimensional media saturation and noise. Experimental footprint measurements are presented and the problems caused by the magnetic nonuniformity of the poles are addressed. The perpendicular overwrite process is studied by time-domain waveform analysis. The spatial distribution of the overwrite signal is determined by the geometry and the magnetic uniformity of the write pole footprint. The dependence of recording parameters on write current overshoot in perpendicular recording is also analyzed.