Measurements and analysis of transition noise in perpendicular media

Transition noise is dominant in high-density magnetic recording using thin-film media. In this paper transition noise is measured for a variety of perpendicular media. Both frequency- and time-domain measurements are utilized. In the frequency domain, the normalized spectra are virtually frequency-independent within the measurement bandwidth corresponding to a dominance of transition jitter. The time-domain measurements yield the transition parameter a and cross-track correlation length s with a knowledge of the read-track width and an assumption of the transition shape. For all media measured, the percentages of the jitter mode are over 70%.