Large spin Hall magnetoresistance and its correlation to the spin-orbit torque in W/CoFeB/MgO structures
arXiv:1505.00899
Abstract
The spin-orbit interaction in heavy metal/ferromagnet/oxide structures has been extensively investigated because it can be employed in manipulation of the magnetization direction by in-plane current. This implies the existence of an inverse effect, in which the conductivity in such structures should depend on the magnetization orientation. In this work, we report a systematic study of the magnetoresistance (MR) of the W/CoFeB/MgO structures and its correlation to the current-induced torque to the magnetization. We observe that the MR is independent of the angle between magnetization and current direction, but is determined by the relative magnetization orientation with respect to the spin direction accumulated by spin Hall effect, which is the same symmetry of so-called spin Hall magnetoresistance. The MR of ~1% in W/CoFeB/MgO samples is considerably larger than those in other structures of Ta/CoFeB/MgO or Pt/Co/AlOx, which indicates a larger spin Hall angle of W. Moreover, the similar W thickness dependence of the MR and the current-induced magnetization switching efficiency demonstrates that they share the same underlying physics, which allows one to utilize the MR in non-magnet/ferromagnet structure in order to understand closely related other spin-orbit coupling effects such as inverse spin Hall effect, spin-orbit spin transfer torques, etc.
References in corpus (17)
- Spin torque switching with the giant spin Hall effect of tantalum
- Spin Hall effect
- Magnetic switching by spin torque from the spin Hall effect
- Current-driven dynamics of chiral ferromagnetic domain walls
- Symmetry and magnitude of spin-orbit torques in ferromagnetic heterostructures
- Spin Hall Magnetoresistance Induced by a Non-Equilibrium Proximity Effect
- Theory of spin Hall magnetoresistance
- Detection and quantification of inverse spin Hall effect from spin pumping in permalloy/normal metal bilayers
- Comparative Measurements of Inverse Spin Hall and Magnetoresistance in YIG|Pt and YIG|Ta
- Quantitative study of the spin Hall magnetoresistance in ferromagnetic insulator/normal metal hybrids
- Indication of intrinsic spin Hall effect in 4d and 5d transition metals
- Spin-orbit torque engineering via oxygen manipulation
- Spin-Hall Magnetoresistance in Platinum on Yttrium Iron Garnet: Dependence on platinum thickness and in-plane/out-of-plane magnetization
- Anomalous temperature dependence of current induced torques in CoFeB|MgO heterostructures with Ta based underlayers
- Exchange magnetic field torques in YIG/Pt bilayers observed by the spin-Hall magnetoresistance
- Intrinsic magnetoresistance in metal films on ferromagnetic insulators
- Anisotropic magnetoresistance driven by surface spin orbit scattering