Abstract
Control of spin–orbit torques (SOTs) in heavy metal/ferromagnetic metal/oxide structures is critical to the realization of promising SOT magnetic random access memory devices. In this paper, the SOT-induced effective fields in Ta/CoFeB/Mg(MgO) structures with perpendicular magnetic anisotropy (PMA) were investigated through the low-current-induced lock-in technique. This paper demonstrates that the industrially preferred MgO preparation method allows us to readily manipulate the oxidation degree of the Mg(MgO) and produce a significant effect on the SOT as well as PMA. Importantly, the ratio of the field-like torque to the damping-like torque efficiency can be controlled without thinning or oxidizing the bottom Ta layer, which is the source of spin-Hall-effect-induced damping-like torque. The achieved ratio of $\sim 2.5$ satisfies the condition that is necessary for the SOT-induced switching without an external magnetic field based on the recently proposed half-precessional switching mechanism.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
