Opt Lett. 2013 Oct 15;38(20):4070-3. doi: 10.1364/OL.38.004070.
We report on the fabrication of a fiber Bragg grating (FBG) with multiple resonances in a two-dimensional waveguide array microstructured optical fiber containing 91 cores. Theoretical investigation reveals that these resonances originate from the identical and nonidentical mode couplings between forward-propagating and backward-propagating LP-like (m=1, 2, 3; LP refers to linearly polarized) supermodes. Since both the central wavelength and minimum transmission of these resonant dips respond differently to curvature and axial strain, this FBG can be applied in the simultaneous measurement of curvature and axial strain.
我们报告了在含有 91 个芯的二维波导阵列微结构光纤中制造具有多个共振的光纤布拉格光栅 (FBG)。理论研究表明，这些共振源于前向传播和后向传播 LP 型（m=1、2、3；LP 表示线性偏振）超模之间的相同和不同模式耦合。由于这些共振峰的中心波长和最小传输都对曲率和轴向应变有不同的响应，因此这种 FBG 可以应用于同时测量曲率和轴向应变。
