Improving the Fourier Modal Method for Crossed Gratings with C4 Symmetry by Use of a Group-theoretic Approach

摘要：

Using a group-theoretic approach that we developed recently we reformulate the Fourier modal method for crossed gratings with C4 symmetry,I. e. The two-dimensionally periodic structures that are invariant after rotations about the normal of the grating plane through angles nπ/2 where n is any integer. With this approach we decompose a crossed-grating problem in some Littrow mountings into four symmetrical basis problems whose field distributions are the symmetry modes of the grating. Then the symmetrical basis problems are solved with symmetry simplifications,whose solutions are superposed to get the field of the original problem. Theoretical and numerical results show that the reformulation improves the computation efficiency effectively: the memory occupation and time consumption are reduced to 1/4 and 1/16 of the original formulation,respectively; for normal incidence, the time-saving ratio is further reduced to 1/32.

作者: Benfeng Bai Lifeng Li

作者单位: Tsinghua University,China

会议类型: 国际会议

会议名称: Progress in Electromagnetics Research Symposium 2005(2005年电磁学研究新进展学术研讨会)(PIERS 2005)

会议地点: 杭州

会议语种:英文

页码: 654-658

在线出版日期: 2005-08-22（万方平台首次上网日期，不代表论文的发表时间）