Cavity magnomechanics with surface acoustic waves

TL;DR

This paper demonstrates a room-temperature, chip-scale cavity magnomechanical system that enables strong magnon-phonon coupling via surface acoustic waves, advancing hybrid spintronic device technology.

Contribution

It introduces a planar cavity magnomechanical system utilizing surface acoustic waves for room-temperature magnon-phonon coupling, a novel approach for integrated spintronic applications.

Findings

Achieved significant back-action effects on cavity frequency and quality factor.

Demonstrated cooperativity exceeding unity, indicating coherent magnon-phonon interaction.

Paved the way for spin-acoustic hybrid technologies in classical and quantum regimes.

Abstract

Magnons, namely spin waves, are collective spin excitations in ferromagnets, and their control through coupling with other excitations is a key technology for future hybrid spintronic devices. Although strong coupling has been demonstrated with microwave photonic structures, an alternative approach permitting high density integration and minimized electromagnetic crosstalk is required. Here we report a planar cavity magnomechanical system, where the cavity of surface acoustic waves enhances the spatial and spectral power density to thus implement magnon-phonon coupling at room temperature. Excitation of spin-wave resonance involves significant acoustic power absorption, whereas the collective spin motion reversely exerts a back-action force on the cavity dynamics. The cavity frequency and quality-factor are significantly modified by the back-action effect, and the resultant cooperativity exceeds unity, suggesting coherent interaction between magnons and phonons. The demonstration of a chip-scale magnomechanical system paves the way to the development of novel spin-acoustic technologies for classical and quantum applications.