Stimulated Brillouin scattering (SBS) lasers based on silicon waveguides with large SBS gain have been widely used in frequency tunable laser emissions, mode-locked pulse lasers, low-noise oscillators, optical gyroscopes and other fields. However, among SBS lasers, the realization of Brillouin laser output often requires a longer waveguide length, which not only increases waveguide loss but also increase the size of the device. As a new medium, lithium niobate has been fabricated into a new type of hybrid structure. Meanwhile, the width of a suspended waveguide is adjusted to tune the phonon frequency of an SBS laser based on lithium niobate substrate. Simulation results show that the tunable forward SBS effect is realized in a lithium niobate-suspended optical waveguide, showing a larger forward stimulated Brillouin scattering gain of 0.31 W⁻¹m⁻¹. The tunable phonon frequency ranges from 1 to 15 GHz. Therefore, utilizing the photon–phonon conversion effect, the waveguide system with LiNbO₃ will pave a new way forward with better integration.

众所周知, 具有高布里渊增益的片上波导在光子学领域具有广泛的应用. 硅基片上布里渊激光器被广泛应用到频率可调谐激光发射、锁模脉冲激光器、低噪声振荡器和光学陀螺仪等领域. 然而, 在硅基布里渊激光器中实现布里渊激光输出往往需要较长的波导长度, 不利于片上集成. 本文提出了一种新型的波导结构, 由硫族化物As₂S₃矩形和一个空气细缝组成. 由于空气细缝的存在, 辐射压力使布里渊非线性的增强远远超过了仅由材料非线性产生的增强. 使得布里渊增益达到了1.78 × 10⁵ W^–1·m^–1, 相比之前报道的后向受激布里渊散射(SBS)增益(2.88 × 10⁴ W^–1·m^–1)扩大了将近10倍, 产生了4.2—7.0 GHz范围的声子频率调谐, 该方法为设计用于前向SBS的纳米级光波导提供了新的思路, 同时这种增强的宽带相干声子发射为片上CMOS信号处理技术的混合铺平了道路.