We first present a bidirectional beam propagation method (BiBPM) based on axially symmetric full-vectorial finite element method (Axi-FVFEM). The Axi-FVFEM based BiBPM is a more versatile method than previous scalar BiBPM for axi-symmetric structure. It has potential to offer more efficient analysis than widely used FEM or finite difference based techniques, especially for a large scale waveguide such as a long periodic structure. An air gap in an axi-symmetric waveguide and a fibre Bragg grating (FBG) are analyzed using the Axi-FVFEM based BiBPM for numerical validation, and we compare the numerical results with those of a 3D finite-difference time-domain (FDTD) method and a modal-based method.

中文翻译：

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基于轴对称全矢量有限元法的双向光束传播方法


我们首先提出了一种基于轴对称全矢量有限元法（Axi-FVFEM）的双向光束传播方法（BiBPM）。基于 Axi-FVFEM 的 BiBPM 是一种比以前的轴对称结构标量 BiBPM 更通用的方法。与广泛使用的 FEM 或基于有限差分的技术相比，它有可能提供更有效的分析，特别是对于长周期结构等大规模波导。使用基于 Axi-FVFEM 的 BiBPM 分析轴对称波导和光纤布拉格光栅 (FBG) 中的气隙进行数值验证，并将数值结果与 3D 时域有限差分 (FDTD) 的数值结果进行比较方法和基于模态的方法。