Magnetic properties of the CoO/Fe(001) system with a bottom-up engineered interface

Abstract Ultrathin CoO films can be grown onto Fe(001) by exploiting Co buffer layers with nanometer thickness, with the result of avoiding the formation of Fe oxides at the interface. Such a system is characterized by a magnetic anisotropy that influences the magnetization reversal behavior, making the Fe easy magnetization axes inequivalent. Here, we exploit Magnetic Second Harmonic Generation to show that such an anisotropy is related to the buried interface and that it is not related to the magnetic properties of the antiferromagnetic CoO layer. In fact, CoO is magnetically ordered already at room temperature, even for low thicknesses and independently on the presence of Fe oxides. The magnetic domains configuration of CoO mimics those of both Fe and Co in all cases, as testified by magnetic PhotoElectron Emission Microscopy measurements.