1:30 PM - 3:30 PM
[24p-P01-9] Current-induced out-of-plane torque in a single permalloy layer controlled by geometry
Keywords:spin orbit torque, Magnetization switching, Magnetoresistive random access memory
Magnetization switching of a ferromagnetic material (FM) with perpendicular magnetic anisotropy (PMA) due to the current-induced torque is expected to improve both durability and device integration of the magnetoresistive random access memory. Recently, current-induced torque via out-of-plane (OOP) spin polarization in a 2D material with broken lateral inversion symmetry in its crystal has been proposed to enable field-free switching of the PMA. However, realization of it with versatile materials is still desirable in terms of industrial application.
In this research, we investigated current-induced torque in a single permalloy layer with broken lateral inversion symmetry in device structure. From the symmetry of the spin-torque ferromagnetic resonance spectrum with respect to magnetic field direction, we estimated four kinds of current-induced torques: in-plane (IP) damping-like (DL), IP field-like (FL), OOP DL, and OOP FL torques. As a result, only the OOP torques that enable field-free switching of the PMA was dependent on the device geometry. Possible origins of the OOP torques are also discussed in our presentation.
In this research, we investigated current-induced torque in a single permalloy layer with broken lateral inversion symmetry in device structure. From the symmetry of the spin-torque ferromagnetic resonance spectrum with respect to magnetic field direction, we estimated four kinds of current-induced torques: in-plane (IP) damping-like (DL), IP field-like (FL), OOP DL, and OOP FL torques. As a result, only the OOP torques that enable field-free switching of the PMA was dependent on the device geometry. Possible origins of the OOP torques are also discussed in our presentation.