Effects of Surface Acoustic Waves in Ferromagnetic Nanostripes

The study of magnetic nanostripes has gained importance in the last decade since this nanostructure is the basic element of proposed non-volatile memory devices. The achievement of the low power control of the magnetization states and the DW dynamics of the nanostripes would mean a considerable step forward for the technological development of these devices. The magnetoelastic effect can be taken advantage of in order to assist the magnetization dynamics in the nanostripes, either in addition or instead of the most common method, the injection of a spin-polarized current. Surface acoustic waves (SAW’s) are able to propagate strain in a periodic fashion and generate changes in the magnetic properties of the nanostructures. SAW’s can induce an additional anisotropy in the direction of propagation of the waves as well as a decrease in the coercive fields of magnetic nanostructures. The application of surface acoustic waves to magnetic nanostructure can also force the magnetic precession of the spins within the ferromagnets and the emission of a spin current in ferromagnetic/non-magnetic bilayers, in analogy to the mechanism of the ferromagnetic resonance