抄録
For a multi-level recording using magnetic field modulation, an exchange coupled film is applied. Therefore it is thought that the critical domain size rc may be different from the rc of a usual MO recording media. However, there is no research to theoretically analyze the rc for multi-level recording using magnetic field modulation. In order to quantitatively analyze the change in rc when changing each of the media constants in a quadri-value recording media, we modified Huth's model. It is clarified that an increase in saturation magnetization Ms, coercivity Hc, and a decrease in interfacial wall energy density σ iw, is effective to make the rc small
