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arXiv · 1301.3431

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

F. Abreu Araujo·L. Piraux·V. A. Antohe·V. Cros·L. Gence
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Abstract

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.

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F. Abreu Araujo, L. Piraux, V. A. Antohe, V. Cros, L. Gence. 2013-01-15. Single spin-torque vortex oscillator using combined bottom-up approach and e-beam lithography. https://doi.org/10.1063/1.4808451

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