【摘要】 交叉波导是集成光学中的一种重要的器件单元 ,针对大角度交叉波导的结构及折射率分布 ,运用基于广义道格拉斯算子的宽角多步有限差分光束传播法模拟大角度交叉波导的传输特性 ,数值计算出波导中的光场的分布。与Crank Nicholson格式的有限差分光束传播法相比 ,该算法在几乎不增加计算时间和计算机内存资源的情况下 ,结合了广义道格拉斯格式的有限差分光束传播法截断误差小 [只有o(Δx) 4 ]和宽角多步法所具有较高精度的优点 ,是光波导器件理想的数值模拟工具。在此基础上计算分析了大角度交叉波导的输出分支波导的能量与交叉角度的关系 ,以及交叉角度对波导间能量耦合的影响。这为实际的设计制作光器件的工作提供了极好的基础更多还原

【Abstract】 Crossing waveguide is an important unit in integrated optics. The generalized Douglas (GD) scheme for variable coefficients is applied to wide-angle multistep finite-difference beam propagation method (FD-BPM). Aiming at the structure and refractive-index profile of wide-angle cross waveguide, the optical field distribution has been calculated by the method. Compared with Crank-Nicholson (CN)scheme in the same computational time and resource, the method has two characteristics: small truncation error of o(Δx) 4 in the transverse direction and high accuracy. It is a useful tool for designing optical waveguide devices. Normalized output optical power versus intersection angle in the main waveguide and power coupling versus intersection angle are analyzed by the method. Numerical result would lay an foundation for authors′ experiment.更多还原