am0c07441_si_001.pdf (762.7 kB)
Giant Spin Hall Effect in Cu–Tb Alloy Thin Films
journal contribution
posted on 2020-07-13, 09:03 authored by Zhan Xu, Grayson Dao Hwee Wong, Jiaxuan Tang, Er Liu, Weiliang Gan, Feng Xu, Wen Siang LewWe
report the giant spin current generation in CuTb alloys arising
from the spin Hall effect. The maximum spin Hall angle from our CuTb-based
magnetic heterostructures was found to be −0.35 ± 0.02
for Cu0.39Tb0.61. We find that the contribution
of skew scattering is larger than the side jump for lower Tb concentrations
(<14.9%), while the converse is true for higher Tb concentrations.
Additionally, we also studied the Gilbert damping parameter, spin
diffusion length, and spin-mixing conductance. Interfacial spin transparency
was found to be 0.55 ± 0.03 for the CoFeB/Cu0.53Tb0.47 interface. The spin diffusion length and spin-mixing conductance
of the Cu0.53Tb0.47 alloy are λsd = 2.5 ± 0.3 nm and G↓↑ = (24.2 ± 1.0) × 1015 cm–2, respectively. Our results pave a way for rare-earth metals to be
used as a spin Hall material in highly efficient SOT devices.
