Recording layer influence on the dynamics of a soft underlayer

This paper addresses the recording layer influence on the dynamics of soft underlayer (SUL) films. The static magnetic properties of soft magnetic films magnetostatically coupled to hard magnetic layers are correlated with their dynamic characteristics. The dynamic behavior is studied both theoretically and via direct experimental observation of the magnetization switching in a soft underlayer driven by a recording head. It is found that the dynamics of a SUL can be strongly influenced by magnetostatic coupling to a recording layer.