Effects of head field pulse shape and rise time on subnanosecond magnetization reversal in longitudinal thin film media

Abstract

Micromagnetic simulations of planar isotropic magnetic thin film recording media are performed to study initial magnetization reversal processes in response to pulses with linear and exponential ramps. Linear ramps lead to smaller zero-crossing times T0 than exponential ramps due to the more rapid field increase during the pulse ramps. It is shown that T0 increases substantially when the pulse amplitude is less than about half the anisotropy field, in which case pulse overshoots are effective to reduce T0. In addition, the effects of exchange coupling and gyromagnetic damping are examined. © 2000 American Institute of Physics.