Abstract
Interparticle interactions in a thin-film recording medium affect the recording characteristics and medium noise. The relation between the exchange coupling of particles and the noise in a perpendicular magnetic recording medium was analyzed with a three-dimensional simulation program. The dc-erased medium noise increases significantly with stronger exchange coupling. However, the change in the noise of a high-density recorded medium resulting from a change in the exchange coupling is not as large. In addition, the exchange coupling increases the playback voltage, because it helps to align the direction of magnetization in the recorded bit area. As a result, the exchange coupling increases the signal-to-noise ratio.
