Fig. 1. (a) Schematic diagram of deep learning model; (b) Schematic diagram of metagrating beam splitter

Fig. 2. Diffraction efficiency and target function of metagrating beam splitter with deflection angle 150°. (a), (d) Average diffraction efficiency and the average target function values of the metagrating beam splitter vs training times; (b), (c) Distribution of diffraction efficiency of the metagrating beam splitter after 100 and 1000 times of training; (e), (f) Distribution of target function values of the metagrating beam splitter after 100 and 1000 times of training

Fig. 3. Structure and the full wave simulation results of the metagrating beam splitter with deflection angle of 120° and 150°; (a), (b) Structure of the metagrating beam splitter with the deflection angle of 120° and 150°; (c), (d) distribution of the metagrating beam splitter with the deflection angle of 120° and 150°; (e), (f) Electric field distribution of the metagrating beam splitter with the deflection angle of 120° and 150° 偏折角为120°和150°时对应的超构光栅分束器结构和全波模拟结果。(a)、(b)偏折角为120°和150°时对应的超构光栅分束器结构；(c)、(d) 偏折角为120°和150°时对应的超构光栅分束器的 分布；(e)、(f) 偏折角为120°和150°时对应的超构光栅分束器的场分布