Computer simulation of hybrid medium for perpendicular magnetic recording

In perpendicular magnetic recording decrease in recording medium noise is one of the most important issues for practical use. One solution is to use a medium with a high squareness. However, such a medium has strong exchange coupling, which results in the increase in medium noise at high recording density. To solve the contradiction we propose a hybrid medium that is composed of two layers, one has strong exchange interaction and the other is an isolated medium. With computer simulation we investigated the read/write characteristics of a hybrid medium. It was found that recording magnetizations of a hybrid medium is kept saturated over 800 kFCI and shows excellent signal-to-noise ratio.