Perpendicular magnetic recording by probe

An investigation has been carried out into perpendicular recording with a cylindrical probe head onto three different types of media: single crystals, coercive media and patterned media. The theory of the recording of cylindrical domains onto single crystal and coercive media has shown many similarities between the processes and similar performances in terms of areal packing densities. The recording of transitions in coercive media and recording onto patterned media has likewise been investigated and expressions are derived for the corresponding packing densities which are much higher than for the recording of cylindrical domains. The critical parameters in all cases are highlighted.