Brillouin-light-scattering imaging of undistorted field distribution and space-time evolution for gigahertz surface phonons

Gigahertz-frequency surface phonons exhibit a large density of states, which can strongly couple to two-dimensional (2D) electronic, magnetic, and excitonic materials on a piezoelectric crystal, facilitating the study of phonon-assisted quantum engineering. Precise imaging of these phonons is crucial for studying their interaction with various carriers or quasiparticles in 2D materials. This study offers a technique for microfocused Brillouin light scattering for high-fidelity, spatiotemporally resolved imaging of the spatial distribution and time evolution of 1D and 2D surface phonons. This approach is a significant tool for designing and characterizing on-chip phononic devices.