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A model is derived to analyze the dynamics of magnetic flux transfer in the pole tip region of a stitched-pole magnetoresistance/thin-film head. Results show three-dimensional vortices inside the pole tips. The motion of the vortex moving in the cross-track direction conducts the flux at the ABS surface. The resulting head field well follows the driving flux with little phase delay and dependence on the damping constant, alpha. Vortex speed under the driving flux remains constant even if the damping constant becomes zero.

This article presents a micromagnetic study of the dynamic magnetic switching process in the pole tip region of stitched-pole thin film write heads. The impacts of track width reduction and pole material saturation moment on the high frequency performance of the heads have been investigated. It is found that the magnetic switching process of the pole tip region at low recording frequencies can be characterized by three stages: the nucleation of a vortex (or vortices), followed by the motion of the vortex (or vortices), and finally the annihilation of the vortex (or vortices). At high frequencies, however, a residual vortex (or vortices) will always remain in the pole tips, resulting in lower head field amplitude. Frequency roll-off characteristics of the head field response have been calculated. The roll off is the result of residual vortex (or vortices), and the vortex moving speed limits the operational frequency range of the head. Reducing the track width lowers the head field 3 dB roll-off frequency. The simulation also finds that the use of 45/55 NiFe, which has significantly higher moment than permalloy, results in higher roll-off frequency as compared to permalloy. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]