Spectral response nulls for single-pole heads in perpendicular recording

This letter discusses the dependence of the nulls in the spectral response function of a single-pole head, used in perpendicular magnetic recording with a double-layer medium, upon the pole thickness and the distance between the pole and the underlayer. Exact results from a two-dimensional model are used to produce approximate but accurate relationships, and are compared with previously published theoretical and experimental results where full data are available.