Presentation Information
[10p-PA3-31]Effect of heavy metal selection on the spin-orbit torque transport properties of skyrmions in CoFeB
〇Takumi Ichinose1, Kohei Yamashita1, Yuichiro Kurokawa1, Hiromi Yuasa1 (1.Kyushu Univ.)
Keywords:
skyrmion
Magnetic skyrmions are promising for low-power spintronics, but controlling their skyrmion Hall angle and skyrmion velocity remains a challenge. We investigated the effects of completely replacing a Ta underlayer with a W underlayer in heavy-metal/CoFeB/MgO stacks. The skyrmion Hall angle was decreased from 46.5 to 33.9 degrees by switching from Ta to W. Crucially, under continuous current, the depinning threshold current density dropped significantly from 33.3x10^8 A/m^2 to 4.17x10^8 A/m^2. Furthermore, while the Ta underlayer required 167x10^8 A/m^2 to reach a skyrmion velocity of 11.1 um/s, the W underlayer achieved a skyrmion velocity of 11.9 um/s at only 16.7x10^8 A/m^2. These results demonstrate that the W underlayer is highly effective for achieving high-speed skyrmion motion while successfully suppressing the skyrmion Hall effect, offering a key strategy for efficient spin-orbit torque devices.