【摘要】 三维级数展开的光束传播法 (3D SEM BPM )将BPM方程转化为一阶常微分方程组 ,具有计算方法简单和计算效率高的优点。运用该法分析了铌酸锂Mach Zehnder结构的电光波导调制器 ,模拟了光场在器件中的分布情况 ,获得了这种调制器模场损耗曲线和最佳结构参数。模拟时引入正切函数变换将无限平面映射为有限平面 ,避免了边界截断问题更多还原

【Abstract】 Three dimensional beam propagation method based on the series expansion method(3D SEM BPM) transform the BPM into the first order normal differential equations. The method has the merits of simple calculation and high calculation efficiency. The lithium niobate electro optic waveguide modulator with Mach Zehnder structure is simulated with this method. We got its optical field distribution and acquired its optimal structure and its power loss curve. The function of tangent is applied to map the infinite space into a finite space to avoid boundary truncation.更多还原