Controlling the written track width in perpendicular recording media

Abstract

Recording simulations were used to determine the factors which influence the recorded track width in perpendicular media. Reducing the width of the main pole and adding side shields to the head are effective methods to write narrower tracks, whilst trailing shields can increase the SNR. Exchange coupling in the recording layer increases the track width, but erase bands are narrowed. However, the magnetisation of a pre-recorded track can influence the switching of grains at the edges of adjacent tracks if the exchange coupling strength is large.