Extended Data Fig. 8: Surface acoustic waves (SAW) generation in LiNbO₃ nanodomain arrays.

a, The diagram of SAW device based on LiNbO₃ nanodomain array. In such LiNbO₃ domain structure (also called acoustic superlattice), the sign of the piezoelectric coefficients is periodically switched, which can produce SAW by using uniform electrodes. The SAW resonant frequency is given by⁶⁷ \(f=\frac{v}{\lambda }\), where \(v\) is the SAW velocity, and \(\lambda \) is the acoustic wavelength that is equal to the period of the LiNbO₃ domain structure. b, The calculated dependence of SAW resonant frequency on the domain period. The SAW velocity is 3718 m/s⁶⁸. For the nanodomain structures with periods of 100 nm and 50 nm, the SAW frequencies reach \(37.2\,{\rm{G}}{\rm{H}}{\rm{z}}\) and \(74.4\,{\rm{G}}{\rm{H}}{\rm{z}}\), respectively.