Reduction in critical current for spin transfer switching in perpendicular anisotropy spin valves using an in-plane spin polarizer

We describe a strategy to reduce spin transfer switching (STS) currents in CoFe/Pd-based perpendicular anisotropy single spin valves (SSVs) by the insertion of an in-plane spin polarizer, thus creating a modified-dual spin valve (m-DSV). For SSV devices, concurrent STS of both magnetic layers was observed for positive currents, making the parallel-to-antiparallel (P -> AP) transition impossible. In m-DSV devices, we observed a 60% reduction in the energy barrier for AP -> P transitions and a 40% reduction in J(c)(AP -> P) with 10 ns STS current pulses compared to SSV devices. Furthermore, the m-DSV structure enabled the soft layer to switch independently from the hard layer via STS.