Design considerations for single-pole type write heads

Summary form only given. We investigated the requirements for a single-pole type (SPT) perpendicular write head and found that certain design trade-offs must be made with respect to the recording media. It is shown through finite element analysis (FEA) that in order to get a high write field, which is what makes perpendicular recording advantageous, a short pole length and small separation distance from the air-bearing surface (ABS) to soft magnetic underlayer (SMUL) are required. However, with a shorter pole length, field gradients deteriorate and the background field increases leading to poorly written bits due to magnetic reversal. The gradients can be improved at the expense of maximum write field. Further complicating the perpendicular write system is non-ideal media. Variations in the media anisotropy enhance the effects of the gradients and background fields. Micromagnetic simulations were carried out for two designs to show these detrimental effects.