Imaging Nonlinear Spin Waves in Magnetoacoustic Nanodevices

High Resolution Image Download MS PowerPoint Slide Hybrid magnetoacoustic material systems offer promising platforms for next-generation sensors and computing applications, but understanding their nonlinear dynamics remains challenging. Here, we use nitrogen vacancy (NV) centers in diamond to spatially map nonlinear magnon scattering processes in FeGaB/LiNbO 3 heterostructures with submicron resolution. We observe highly heterogeneous magnetic noise generation under acoustic driving at 1425 MHz, with responses varying dramatically across micron length scales. Time-domain measurements reveal threshold-like nonlinear behavior where NV center spin relaxation rates increase over 2 orders of magnitude as drive power is increased. These findings reveal microscopic noise sources that limit magnetoacoustic sensor performance while simultaneously demonstrating how material engineering and acoustic mode design could enable selective control of nonlinear magnon processes.