Slot waveguides based on silicon-on-insulator dielectric material are investigated theoretically for structural optimization with the aim of attaining the maximum light confinement with the minimum mode footprint inside the slot region. The effects of various geometrical parameters on the field confinement factor and effective mode area are examined to determine the performance of dielectric vertical- and horizontal-slot waveguides. Parametric analysis for the optimization of the slot waveguides is carried out using the finite element method (FEM). The theoretical and FEM-based electric/magnetic field components and Poynting vector profiles are compared for both types of slot waveguide. Furthermore, a cross-slot structure is proposed based on the optimized parameters found for the vertical- and horizontal-slot waveguides, to guide both quasi-transverse electric (TE) and quasi-transverse magnetic (TM) modes simultaneously. For the cross-slot waveguide with optimized dimensions, the numerical simulation predicts a confinement factor of ~ 34.16% with an effective mode area of ~ 0.438 μm² in the quasi-TE mode and ~ 30.12% with 0.480 μm² in the quasi-TM mode.

中文翻译：

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SOI光缝波导的结构优化和参数分析

从理论上研究了基于绝缘体上硅介电材料的缝隙波导，以进行结构优化，目的是在缝隙区域内以最小的模式足迹获得最大的光限制。研究了各种几何参数对场限制因子和有效模式面积的影响，以确定电介质垂直槽和水平槽波导的性能。使用有限元方法（FEM）进行用于优化缝隙波导的参数分析。比较了两种缝隙波导的理论和基于FEM的电场/磁场分量和Poynting矢量轮廓。此外，根据针对垂直和水平槽波导找到的优化参数，提出了一种交叉槽结构，同时引导准横向电（TE）模式和准横向磁（TM）模式。对于具有最佳尺寸的十字槽波导，数值模拟预测有效模量约为0.438μm的限制因子约为34.16％²在准TE模式和〜30.12％与0.480微米²在准TM模式。