Phys.org March 29, 2024
An international team of researchers (Japan, Austria, Spain) observed strong coupling between magnons and surface acoustic wave (SAW) phonons in a thin CoFeB film constructed in an on-chip SAW resonator by analyzing SAW phonon dispersion ant crossings. They used a nanostructured SAW resonator design that allowed them to enhance shear-horizontal strain. This type of strain couples strongly to magnons. Their device design provided the tunability of the film thickness with a fixed phonon wavelength, which was a departure from the conventional approach in strong magnon-phonon coupling research. They detected a monotonic increase in the coupling strength by expanding the film thickness, which agreed with their theoretical model. According to the researchers their work provides a significant way to advance fundamental research and the development of devices based on magnon-phonon hybrid quasiparticles… read more. TECHNICAL ARTICLE
Schematic illustration. Credit: Phys. Rev. Lett. 132, 056704, 31 January 2024