Near-Unity Spin Hall Ratio in Ni${}_x$Cu${}_{1-x}$ Alloys

Abstract

We report a large spin Hall effect in the 3$d$ transition metal alloy Ni${}_x$Cu${}_{1-x}$ for $x\in \left\{0.3,0.75\right\}$, detected via the ferromagnetic resonance of a Permalloy (Py = Ni${}_{80}$Fe${}_{20}$) film deposited in a bilayer with the alloy. A thickness series at $x$ = 0.6, for which the alloy is paramagnetic at room temperature, allows us to determine the spin Hall ratio ${\theta }_{\mathrm{SH}}\approx 1$, spin diffusion length ${\lambda }_{\mathrm{s}}$, spin mixing conductance $G_{\uparrow \downarrow }$, and damping ${\alpha }_{\mathrm{SML}}$ due to spin memory loss . We compare our results with similar experiments on Py/Pt bilayers measured using the same method. Ab initio band structure calculations with disorder and spin-orbit coupling suggest an intrinsic spin Hall effect in Ni${}_x$Cu${}_{1-x}$ alloys, although the experiments here cannot distinguish between extrinsic and intrinsic mechanisms.

arXiv commentNew ab initio calculations of Ni-Cu alloy band structure added; new author; new fig in main text and new appendix describing calculations

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Cited by in corpus (10)

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• Compositional effect on auto-oscillation behavior of Ni100-xFex/Pt spin Hall nano-oscillators
• Independence of the inverse spin Hall effect with the magnetic phase in thin NiCu films
• Perspectives on spin hydrodynamics in ferromagnetic materials
• Vertically Graded Fe-Ni Alloys with Low Damping and a Sizeable Spin-Orbit Torque
• Absorption of Transverse Spin Current in Ferromagnetic NiCu: Dominance of Bulk Dephasing over Spin-Flip Scattering
• Spin wave excitations in a nanowire spin-torque oscillator with perpendicular magnetic anisotropy
• Spin-orbit torques and magnetization switching in Gd/Fe multilayers generated by current injection in NiCu alloys
• Resonant Measurement of Non-Reorientable Spin-Orbit Torque from a Ferromagnetic Source Layer Accounting for Dynamic Spin Pumping
• Large Spin Nernst Effect in Ni70Cu30 Alloy