Gain and acoustic characteristics of inter-mode forward stimulated Brillouin scattering (FSBS) induced by discrete vector high-order optical mode (HOM) pairs in a few-mode nanofiber (FMNF) are presented in this paper. Three completely different acoustic modes of TA₀₂, R₂₂, and R₂₁ preferentially interact with the TE₀₁–TM₀₁, TE₀₁–HE₂₁, and TM₀₁–HE₂₁ mode pairs, respectively, and dominate the highest Brillouin peak at different frequencies. Moreover, the influence of FMNF radius on Brillouin gain spectrum (BGS) characteristics is also investigated. The R₂₁-caused Brillouin peak in the BGS of TM₀₁–HE₂₁ is much higher than that of TE₀₁–TM₀₁ (TE₀₁–HE₂₁). Especially, the R₂₁ acoustic mode that interacts with the TM₀₁–HE₂₁ mode pair can provide the maximum Brillouin gain, which is also the highest peak at frequency ranges greater than 1 GHz, compared with all inter-mode and even intra-mode BGSs. And a definite functional relationship is found between the incident wavelength, the optimal FMNF radius, and the maximum of R₂₁-caused Brillouin gain. Vector HOMs induced inter-mode FSBS may provide a promising approach for applications, such as sensing and nonlinear dynamics of the Brillouin interaction.

本文介绍了由离散矢量高阶光模 (HOM) 对在少模纳米纤维 (FMNF) 中引起的模间前向受激布里渊散射 (FSBS) 的增益和声学特性。TA ₀₂、R ₂₂和R ₂₁三种完全不同的声学模式分别优先与TE ₀₁ –TM ₀₁、TE ₀₁ –HE ₂₁和TM ₀₁ –HE ₂₁模式对相互作用，并在不同的条件下支配最高布里渊峰频率。此外，还研究了 FMNF 半径对布里渊增益谱 (BGS) 特性的影响。R ₂₁TM ₀₁ –HE ₂₁的BGS 引起的布里渊峰远高于TE ₀₁ –TM ₀₁ (TE ₀₁ –HE ₂₁ )。特别是，与 TM ₀₁ –HE ₂₁模式对相互作用的 R ₂₁声模式可以提供最大布里渊增益，与所有模式间甚至模式内相比，这也是大于 1 GHz 的频率范围内的最高峰值BGS。并在入射波长、最佳 FMNF 半径和 R ₂₁的最大值之间找到了明确的函数关系- 引起布里渊增益。矢量 HOM 诱导的模式间 FSBS 可能为应用提供一种有前途的方法，例如布里渊相互作用的传感和非线性动力学。