Spin-torque vortex oscillators in multilayered metallic nanowires electrodeposited inside nanoporous alumina templates: experimental measurements and micromagnetic study

We report on microwave oscillations induced by spin-transfer-torque in metallic spin-valves obtained by electrodeposition of Co-Cu-Co trilayer structures in nanoporous alumina templates. Using micromagnetic calculations performed on similar spin-valve structures it was possible to identify the magnetization dynamics associated with the experimentally determined microwave emission. Furthermore it appears that in our particular geometry the microwave emission is generated by the vortex gyrotropic motion which occurs in, at least, one of the two magnetic layers of our spin-valve structures. Microwave emission was obtained in the absence of any external magnetic field with the appropriate magnetization configuration.