| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Nanomaterials | Monday Sessions |
| Session NM-MoM |
| Session: | Magnetic Properties |
| Presenter: | Teruo Ono, Kyoto University, Japan |
| Correspondent: | Click to Email |
Current-induced magentic domain wall motion has been attracted much attention both from scientific and technological points of view [1]. When a magnetic DW is driven by electric current via adiabatic spin torque, the theory predicts a finite threshold current even for a perfect wire without any extrinsic pinning [2]. We have shown that this intrinsic pinning determines the threshold current, and thus that the adiabatic spin torque dominates the DW motion resulting in DW motion along electron flow direction, in a perpendicularly magnetized Co/Ni system sandwiched by a symmetric capping and seed layers [3-9]. On the other hand, current-induced DW motion against electron flow direction has been observed in ultrathin magnetic films in which the structural inversion symmetry (SIA) was broken [10, 11]. Recently, this DW motion against electron flow direction has been explained by the combination of a chiral DW and spin Hall torque [12, 13].In this presentation, I will show the systematic investigation by changing thickness of Co/Ni layer and discuss the contribution of adiabatic spin transfer torque, and spin Hall torque in the current-induced DW motion. I will also discuss possible applications using the current-induced DW motion.
This work was partly supported by a Grant-in-Aid for Scientific Research on Innovative Areas, Grant-in-Aid for Specially Promoted Research, and R & D Project for ICT Key Technology of MEXT.
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