Initial Magnetization Curve and Magnetic Domain Pattern of Co/Pt Multilayered Thin Film

[[abstract]]This study inquires into the relationships between the initial magnetization curve and the magnetic domain pattern in the demagnetized states for multilayered Co/Pt thin film samples. The magnetic domain pattern for the sample demagnetized by an in-plane magnetic field and for the sample demagnetized by a perpendicular magnetic field were found to be quite different even though both states have zero magnetization. The former state has denser and finer domains than the latter. The initial magnetization for the fine domains increases with an increase in magnetic field, while for the coarse domains, the initial magnetization remains at zero for magnetic field below coercivity Hc, then rises sharply to saturated magnetization when magnetic field is nearly equal to Hc. Moreover, the magnetic domain pattern for the sample demagnetized by an in-plane magnetic field can be use to estimate the domain wall energy as long as the domain size is know