Using bilayer films of-Ta (5 nm)/Ni0.8Fe0.2 (2 nm), we fabricate elliptical structures which exhibit uniaxial magnetic anisotropy, resulting in single magnetic domain behavior. We study induced spin-orbit torques (SOTs) in these devices with first-and second-order harmonic Hall measurements for current flowing along the long axis of the ellipses and external magnetic field applied in the film plane. We observe a giant response to the SOTs associated with magnetization reversal of the NiFe layer, and we correlate it quantitatively with a d phi m/d phi H term, where phi m and phi H are the in-plane angles of the magnetization and the magnetic field, respectively. We discuss theoretical and applicative implications of this intriguing behavior.
Bibliographical notePublisher Copyright:
© 2022 American Physical Society.