Stimulated Brillouin scattering by surface acoustic waves in lithium niobate waveguides

We numerically demonstrate that Lithium Niobate on Insulator (LNOI) waveguides may support confined short-wavelength surface acoustic waves interact strongly with optical fields through backward stimulated Brillouin scattering in both $Z$ and $X$-cut orientation. conduct fully anisotropic simulations consider not only moving boundary photoelastic forces, but also roto-optic forces for the interaction. Our results indicate photoelasticity dominates gain can reach as high $G_{B}/Q_{m}$ = 0.43 W$^{-1}$m$^{-1}$ standard ridge