Spinmotive force in the out-of-plane direction generated by spin wave excitations in an exchange-coupled bilayer element

The generation of the spinmotive force (SMF) requires the temporal and spatial variations of the magnetic moments. We explore an approach to satisfy this requirement by creating asymmetry in a thin film structure along the out-of-plane direction, through the use of an exchange-coupled L1(0)-FePt/Ni81Fe19 bilayer element. As the spin wave is excited by a rf magnetic field, a continuous dc voltage signal in the out-of-plane direction of the bilayer element appears. The sign of the voltage signal and its microwave power dependency agree with the theoretical framework of the SMF. The corresponding spin wave modes are revealed by carrying out the micromagnetic simulation. Our results demonstrate the generation of the SMF using a vertically structured element in addition to previously reported in-plane structured devices.