Spin transfer switching characteristics in a [Pd/Co]m/Cu/[Co/Pd]n pseudo spin-valve nanopillar with perpendicular anisotropy

We successfully demonstrate spin transfer switching (STS) characteristics in a [Pd/Co](m)/Cu/[Co/Pd](n) pseudo spin-valve nanopillar with 100 nm diameter. We observed lower critical current density and high giant magnetoresistance (GMR) ratio in our devices compared to other fully perpendicularly magnetized pseudo spin-valve structures. The devices showed a current-perpendicular-to-plane GMR of 1.2% and a STS critical current density of J(AP-P) = -2.6 x 10(7) A/cm(2) and J(P-AP) = 3.8 x 10(7) A/cm(2). The observed low critical current density is thought to be due to higher spin-transfer efficiency arising from smaller spin orbital scattering, longer spin diffusion length of the thinner Pd, and thinner soft-layer-film thickness and coercivity in the nanopillar devices. (C) 2012 American Institute of Physics. [doi:10.1063/1.3675150]