Origin of magnetic anisotropy, role of induced magnetic moment, and all-optical magnetization switching for Co_100?<i>x</i>Gd_<i>x</i>/Pt multilayers

The combination of Co, Gd, and Pt materials is a representative with perpendicular magnetic anisotropy (PMA) for the all-optical switching (AOS), which provides promising route ultrafast magnetization manipulation. This paper shows that PMA Co100?xGdx/Pt multilayers mainly originates not from bulk property ferrimagnetic Co100?xGdx but interface between layers. In addition, contribution moment induced in becomes remarkable, modulates compensation temperature samples thin exhibited helicity-independent wide range Gd concentrations, maximum AOS probability was achieved near composition. We discuss correlation properties multilayers. showed clear thickness dependence, attributable to remarkable moment. Our findings are beneficial only understanding mechanism also designing spintronic devices using ferrimagnets.