The interaction between Surface Acoustic Waves (SAW) and Spin Waves (SW) in heterostructures composed of piezoelectric and magnetostrictive materials will be discussed in the framework of the SAW-induced Ferromagnetic Resonance (FMR) and SW-generation. It is well established that Interdigitated Transducers (IDT) exciting SAW in the GHz and sub-GHz regime in a piezoelectric media (see IDT in Fig.1), permit SAW-FMR in ferromagnetic thin films, as Ni and GaMnAs. [1,2] Here, I will focus on recent experiments on Fe thin films epitaxied on a piezoelectric GaAs(001) substrate that have demonstrated efficient resonant MEC through SAW.[3,4] This study investigates the impact of an external magnetic field on the velocity and the amplitude of surface acoustic waves (SAWs). The SAW velocity is found to be strongly influenced by both the amplitude and direction of the magnetic field. To explain these observations, the study employs a phenomenological model that considers the relative change in SAW velocity, with a key factor being the inclusion of spin-wave dispersion. The validity of this model is confirmed through comparisons with a fully magnetoelastic model. Additionally, the study explores the nonreciprocity of SAWs’ propagation both experimentally and theoretically. Concerning magnonic applications, we note that SAWs can propagate over long distances in piezoelectric materials like LiNbO3 or GaAs. Consequently, SAWs generated by a single Interdigital Transducer (IDT) may interact with thousands of magnonic circuits since SAW spread over millimetres square in a well-controlled manner. These experiments suggest the integration of SAW-FMR mechanism in magnonic devices where SWs, generated by antennas or by dynamic strain could be locally handled, triggered, scattered or even suppressed by SAWs excited, in turn, by remote voltage-driven IDTs.

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