Single spin-torque vortex oscillator using combined bottom-up approach and e-beam lithography

• Published in: Applied physics letters Vol. 102; no. 22
• Main Authors: Abreu Araujo, F., Piraux, L., Antohe, V. A., Cros, V., Gence, L.
• Format: Journal Article
• Language: English
• Published: 03-06-2013
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4808451

A combined bottom-up assembly of electrodeposited nanowires and electron beam lithography technique has been developed to investigate the spin transfer torque and microwave emission on specially designed nanowires containing a single Co/Cu/Co pseudo spin valve. Microwave signals have been obtained even at zero magnetic field. Interestingly, high frequency vs. magnetic field tunability was demonstrated, in the range 0.4–2 MHz/Oe, depending on the orientation of the applied magnetic field relative to the magnetic layers of the pseudo spin valve. The frequency values and the emitted signal frequency as a function of the external magnetic field are in good quantitative agreement with the analytical vortex model as well as with micromagnetic simulations.