Effect of throat height reduction in gapped heads

This paper describes an investigation, based on finite-element models, of the effect of throat height reduction in gapped heads constructed from realistic, saturable materials. It considers materials and two gap region geometries. It shows that throat height reduction in a gapped head improves both the maximum horizontal field and the maximum horizontal field gradient provided that saturation does not partially block the flux path toward the gap. Saturation of planar heads limits both the maximum horizontal field and the maximum horizontal field gradient at higher throat heights than it does in conventional gapped heads. The paper shows that the optimum write field of a conventional gapped head is both stronger and sharper than that of a planar one.