Spin transport in memristive devices

We report on electron spin transport through electrochemically precipitated copper filaments formed in TaOx memristive devices consisting of Co/TaOx/Cu/Py with crossbar-type electrode geometry. The devices show memristive behavior having a typical OFF/ON resistance ratio of 10(5). Magnetoresistance measurements performed by sweeping an external magnetic field clearly indicate spin transport through an electrochemically formed copper nano-filament as long as 16 nm in the memristive ON-state at 77 K. Spin transport vanishes in the OFF-state. These data are strong evidence that the fundamental switching mechanism in these metal-oxide devices is the formation of continuous metallic conduction paths. (C) 2012 American Institute of Physics. [doi:10.1063/1.3679114]