Coercivity of ultrathin magnetic films with perpendicular anisotropy

The calculation of the temperature dependence of the domain wall coercivity of ultrathin magnetic films with perpendicular anisotropy is reported. In this case, the magnetization reversal is supposed to occur through domain w all motion. The proposed model takes into account thermal bending fluctuati ons of the domain wall, which is pinned by crystal defects such as grain bo undaries. A fitting procedure, applied to recently published experimental d ata on the field induced domain wall velocity in Au/Co films, allows us to find out realistic values of the involved parameters.