面向光纤多模选择性激发的电磁超表面设计

针对光纤中多个模式的选择性激发问题，提出利用介质超表面实现光纤多模的频率选择性激发方案. 将超表面结构分为四个象限区，对前三象限超表面结构采用便利搜索法设计，对第四象限结构采用深度学习方法进行反向设计，实现了频率控制两个模式的模分复用. 该方案为实现光纤多模复用提供了一种新的思路，且选择性激发的模式个数具有可拓展性；在通信领域具有潜在的应用前景.

Electromagnetic metasurface design for multi-mode selective excitation in fiber communication system

How to realize the selective excitations of different optical modes in fibers is a key problem in mode division multiplexing. Here, a silicon metasurface is designed for realizing the multi-mode selective excitation at different frequencies. The metasurface is divided into four quadrants. We design the first three quadrants with the traversal searching method, and the fourth quadrant with deep learning. Consequently, two fiber modes are locked at different frequencies, and selectively excited. This proposal provides a new approach for selective excitation of fiber modes, and it can be extended to more modes. It shows promising applications in optic communications.