Surface acoustic wave stimulated Brillouin scattering in thin-film lithium niobate waveguides

We report the first-ever experimental observation of backward stimulated Brillouin scattering (SBS) in thin-film lithium niobate (TFLN) waveguides. The peak Brillouin gain coefficient of the z-cut LN waveguide with a crystal rotation angle of 20${}^{\circ }$ is as high as 84.9m${}^{-1}$W${}^{-1}$, facilitated by surface acoustic waves (SAW) at 8.06GHz.