T. Min et Jg. Zhu, GRAIN HEIGHT FLUCTUATION AND MEDIUM NOISE IN LONGITUDINAL THIN-FILM RECORDING MEDIA, IEEE transactions on magnetics, 29(6), 1993, pp. 3706-3708
The effect of grain height variation on medium noise at small head-med
ium spacing has been studied by micromagnetic modeling. The reverse dc
erasure process using a thin film head at low-fly height is simulated
for two types of films: a film with grain height fluctuation and a fi
lm with identical grain height. Results show that grain height variati
on at microscopic scale does not significantly affect the noise behavi
or of the thin film media and the domain widths are mainly determined
by magnetic interactions. Calculations show that the magnetization cro
ss track correlation lengths for both films are essentially the same.
The noise power as a function of erasure field exhibits a linear relat
ion with the field derivative of the remanent hysteresis curve, consis
tent with recent experimental results.