Effect of Mg Oxidation Degree on Rashba-Effect-Induced Torques in Ta/CoFeB/Mg(MgO) Multilayer
Autor: | Amal El-Ghazaly, Shan X. Wang, Noriuki Sato, Robert M. White |
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Rok vydání: | 2016 |
Předmět: |
010302 applied physics
Materials science Condensed matter physics Oxide 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Electronic Optical and Magnetic Materials Magnetic field Metal Condensed Matter::Materials Science Magnetization chemistry.chemical_compound chemistry Ferromagnetism visual_art 0103 physical sciences Oxidizing agent visual_art.visual_art_medium Torque Electrical and Electronic Engineering 0210 nano-technology Rashba effect |
Zdroj: | IEEE Transactions on Magnetics. 52:1-4 |
ISSN: | 1941-0069 0018-9464 |
Popis: | 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. |
Databáze: | OpenAIRE |
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