3D analysis of MR readback on perpendicular medium

A 3-D analysis of magnetoresistive (MR) read on perpendicular media using the reciprocity method is presented. It is shown that the conduction of magnetic flux, obtained from an equivalent reciprocity field, away from the active area is an important phenomenon for this structure, and may introduce error if 2-D analysis is used. The authors examine the effect of shield width and show that when the shield width is equal to the width of the active area of the MR head, 3-D analysis closely resembles the 2-D results. This calculation is extended to a differentially connected dual element MR head for perpendicular recording