Determination of the magnetic anisotropy constant of Cu/Fe/SiO₂/Si by a magneto-optical Kerr effect susceptometer

The magneto-optical Kerr effect susceptometry technique is proposed to determine the uniaxial magnetic anisotropy (UMA) constant K_u. The magnetic properties of Cu/Fe/SiO₂/Si grown by dc magnetron sputtering were investigated. The in-plane uniaxial magnetic anisotropy was probed by the magneto-optical Kerr effect (MOKE). The value of UMA, K_u=2.5×10³ J/m³, was simulated from the field dependence of ac susceptibility along the hard axis according to the Stoner–Wohlfarth (S–W) model, which is consistent with K_u=2.7×10³ J/m³ calculated from the magnetic hysteresis loops. Our results show that the magneto-optical Kerr effect susceptometry can be employed to determine the magnetic anisotropy constant owing to its high sensitivity.