Voltage-induced coercivity change in FePt/MgO stacks with different FePt thicknesses

We studied magnetic properties by applying electric voltage (Vapp) to FePt/MgO stacks with different FePt thicknesses (tFePt), where tFePt was varied in the range from 0.6 to 1.5?nm. The change in coercivity (Hc) became remarkable when tFePt was reduced, and a change in Hc of 45?Oe was achieved for tFePt?=?0.6?nm by changing Vapp in the range from +5 to ?13?V. However, the resistance change of the anomalous Hall effect remained almost constant regardless of Vapp. These experimental results suggest the possibility of interface magnetic anisotropy between FePt and MgO being modulated in the present devices by applying Vapp, which leads to voltage-induced change in Hc in the FePt layer.