On-chip stimulated Brillouin scattering[Invited]

On-chip stimulated Brillouin scattering(SBS)has attracted extensive attention by introducing acousto-optic coupling interactions in all-optical signal processing systems.A series of chip-level applications such as Brillouin lasers,amplifiers,gyroscopes,filters,and nonreciprocal devices are realized based on Brillouin acousto-optic interaction.Here,we first introduce the fundamental principle of SBS in integrated photonics and a method for calculating Brillouin gain;then we illustrate the Brillouin effect on different material platforms with diverse applications.Finally,we make a concise conclusion and offer prospects on the future developments of on-chip SBS.