We propose an experimental scheme to determine the spin-transfer torqueefficiency excited by the spin-orbit interaction in ferromagnetic bilayers fromthe measurement of the longitudinal magnetoresistace. Solving a diffusivespin-transport theory with appropriate boundary conditions gives an analyticalformula of the longitudinal charge current density. The longitudinal chargecurrent has a term that is proportional to the square of the spin-transfertorque efficiency and that also depends on the ratio of the film thickness tothe spin diffusion length of the ferromagnet. Extracting this contribution frommeasurements of the longitudinal resistivity as a function of the thickness cangive the spin-transfer torque efficiency.
展开▼
