Modeling the effects of write field rise time on the recording properties in thin film media

A theory for including the effect of finite write field rise time in the calculation of written transition parameters for thin film media has been developed. Calculated dependence of transition parameter overwrite and nonlinear transition shifts on the write field rise time are shown. Model results are compared with measured values for a thin film inductive head at different write current rise times and varying disk rotational velocity for fixed linear density and flying height. The theory has also been used to calculate the amount of precompensation required to reduce the nonlinear shift to near zero.