Optimization of Pt-based spin-Hall-effect spintronic devices

We study experimentally the routes to improve the characteristics of the spin-Hall-effect devices based on permalloy/Pt bilayers by optimization of the Pt layer thickness and by the addition of an antiferromagnetic spin-sinking layer. We experimentally determine the spin-diffusion length in Pt and show that Pt thickness can be reduced down to 2 nm without degradation of the device characteristics caused by the spin accumulation effects, which provides possibilities for significant reduction of the required driving currents. We also show that the addition of a spin-sinking layer results in a non-monotonic dependence of device efficiency on the Pt thickness. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4799492]