Domain Patterns and Magnetization Reversal Behaviors in Oxide/Co/Pt Films

The domain patterns and magnetization reversal behaviors in oxide/Co/Pt films are examined with varying the thickness of Co layer from 0.7 nm to 2.0 nm. The films are grown on Al₂O₃, MgO and SiO₂ layers. All the films exhibit strong perpendicular magnetic anisotropy, but the anisotropy decreases with increasing Co layer thickness for all the oxide layers. The decrement rate is different for different oxide layers. The domain patterns show the transition between the wall-motion and dendrite-growth dominant behaviors, and the critical thickness is estimated to be about 1.0 nm irrespective of the oxide layers. We summarize the magnetic properties of oxide/Co/Pt films with respect to the Co-thickness and various oxide layers.