Current-induced magnetization switching in perpendicularly magnetized V/CoFeB/MgO multilayers

Abstract

The perpendicular magnetic anisotropy properties of CoFeB/MgO films on $3d$ light-metal vanadium have been experimentally investigated. The interfacial magnetic anisotropy is $1.4\phantom{\rule{0.16em}{0ex}}\mathrm{erg}/\mathrm{c}{\mathrm{m}}^{2}$ for the V/CoFeB/MgO multilayers annealed at 240 \ifmmode^\circ\else\textdegree\fi{}C. A sign change of the effective torque fields with the increase of V thickness has been observed, which is confirmed by current-induced magnetization switching measurements, suggesting a competition of multiple effects on current-induced torques in the weakly spin-orbit coupled V/CoFeB/MgO multilayers. These findings have implications for the fundamental understanding of current-induced torque and further device applications using $3d$ light transition-metal based heterostructures.