Computer simulation of magnetic wall induced in under-layer by SPT head field

Summary form only given. Using computer simulation we have proposed a novel perpendicular recording medium (hybrid medium) of which the recording layer comprises stacked layers of a continuous and an isolated film. We showed the medium has a possibility to solve simultaneously thermal stability and high-density recording ability. Several experiments have verified the excellent recording and thermal properties under well-adjusted conditions. However, the medium noise still remained to be solved, especially the noise from the under-layer. In a recording simulation unique magnetic domain walls in an under-layer often emerged and they enhanced medium noise. We investigated its cause and the procedure to prevent the occurrence.