09:30 〜 09:45
▲ [11a-M101-3] Spin torque induced by orbital conversion at Cu/Al2O3 interface
キーワード：Spin conversion, Rashba effect, Orbitronics
Despite the recent astonishing progress on the spin conversion induced by the spin-orbit interaction (SOI), there is an obstacle for further applications due to material limitation to heavy elements. Here we report an alternative mechanism of the charge-to-spin conversion in ferromagnetic metal (FM)/Cu/Al2O3 structures by a key role of the orbital moment.
The charge-to-spin conversion was observed by the spin torque ferromagnetic resonance (ST-FMR) technique. In this study, observed spin torque efficiency reaches up to ~0.3, which corresponds to the largest efficiency from heavy metals [1]. It is a surprising result considering that none of the heavy element was included in this structure. One possible mechanism of this result is the generation of the orbital moment at the orbital textured Cu/ Al2O3 interface by the orbital Rashba effect [2]. The generated orbital moment is converted to the spin, and it exerts a torque for the magnetization of the FM.
[1] Pai et al., Appl. Phys. Lett. 101, 122404 (2012).
[2] Park et al., Phys. Rev. Lett. 107, 156803 (2011).
The charge-to-spin conversion was observed by the spin torque ferromagnetic resonance (ST-FMR) technique. In this study, observed spin torque efficiency reaches up to ~0.3, which corresponds to the largest efficiency from heavy metals [1]. It is a surprising result considering that none of the heavy element was included in this structure. One possible mechanism of this result is the generation of the orbital moment at the orbital textured Cu/ Al2O3 interface by the orbital Rashba effect [2]. The generated orbital moment is converted to the spin, and it exerts a torque for the magnetization of the FM.
[1] Pai et al., Appl. Phys. Lett. 101, 122404 (2012).
[2] Park et al., Phys. Rev. Lett. 107, 156803 (2011).