Resonant Magnetization Switching Conditions of an Exchange-coupled Bilayer under Spin Wave Excitation

Abstract

We systematically investigated the spin wave-assisted magnetization switching (SWAS) of a L10-FePt / Ni81Fe19 (Permalloy; Py) exchange-coupled bilayer using a pulse-like rf field (hrf) and mapped the switching events in the magnetic field (H) - hrf frequency (f) plane to reveal the switching conditions. The switching occurred only in a limited region following the dispersion relationship of the perpendicular standing spin wave (PSSW) modes in Py. The results indicate that SWAS is a resonant magnetization switching process, which is different from the conventional microwave assisted switching, and has the potential to be applied to selective switching for multilevel recording media.