CNR-Istituto Officina dei Materiali (IOM), Basovizza (TS), 34149, Italy
The significant increase in the production of electronic devices and the continuous demand for more efficient, high-capacity, and faster systems have increasingly highlighted the limitations of conventional electronics, fully confirming the predictions of Moore’s law. As a result, new fields of research have become necessary, and among the most promising is spintronics, where exploiting the quantum property of electron spin could overcome the current limitations of electronics.
In recent years, particular attention has been devoted to the generation and control of spin waves through magneto-acoustic coupling or direct interaction with light. Here, I present an all-optical method for the excitation of coherent magnons in the GHz range, with precise control over their wavevector, based on a four-wave-mixing approach known as the Transient Grating technique. Applications to various materials are discussed, demonstrating both direct and indirect excitation mechanisms of spin waves.
Furthermore, the coupling between spin waves and acoustic waves is investigated using the magneto-optical Kerr effect in engineered materials. The use of both tabletop and free-electron laser-based techniques is also explored, highlighting the versatility of the transient grating approach.