光栅衍射特性的耦合波分析、计算与讨论

本文从麦克斯韦方程组及电磁场边界条件出发,推导了广泛应用于各类光栅衍射问题的矢量分析方法--严格的耦合波分析方法.针对光栅的衍射特性,编写了基于严格的耦合波分析方法的计算程序,并以TE模情形为例对光栅的衍射效率和收敛性作了数值计算.结果表明,当谐波数不断增加,即便对于厚光栅(d/λ>10)情形,光栅的衍射效率仍将收敛于某一确定值.

Coupled-wave Analysis, Numerical Calculation and Discussion for Diffraction Properties of Grating

Rigorous coupled-wave analysis method based on vector theory analysis is derived and discussed by using Maxwell equations and electromagnetic boundary conditions. A general diffraction analysis numerical code based on the Rigorous Coupled-wave Analysis (RCWA) is written so as to design and analyze the diffraction properties of grating, and the diffraction efficiency and the convergence of the RCWA are investigated for the TE mode. The calculated diffraction efficiency is shown to converge to the correct value with an increasing number of space harmonies over a wide range of parameters, including very deep gratings (d/λ>10).