A polarization-insensitive four-port beam splitter based on the plus-shaped ridge structure is introduced. The ridge of this grating is a plus-shaped resin material. Based on the rigorous coupled-wave analysis and the simulated annealing algorithm, the transmission efficiency of the zeroth order under TE polarization is 1.79%, and the efficiencies of 22.21%/22.19% for the ± first/± second orders are diffracted. Meanwhile, the transmission efficiency of the zeroth order under TM polarization is 0.13%, and the efficiencies of 23.25%/23.23% for the ± first/± second orders are diffracted. In addition, the diffraction efficiency of each order is computed while the wavelength, grating period, and duty cycle are varied around the optimized parameters. The study reveals that the grating has excellent tolerance and stability. Hence, it is inferred that plus-shaped ridge four-port grating exhibits promising potential for advancement in the field of lasers.

中文翻译：

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1 × 4 分路器正形结构的结构和表征

介绍了一种基于加号脊结构的偏振不敏感四端口分光器。该光栅的脊部是加号形状的树脂材料。基于严格的耦合波分析和模拟退火算法，TE偏振下零阶传输效率为1.79%，±一阶/±二阶衍射效率为22.21%/22.19%。同时，TM偏振下零阶传输效率为0.13%，±一阶/±二阶衍射效率为23.25%/23.23%。此外，当波长、光栅周期和占空比围绕优化参数变化时，计算每个级次的衍射效率。研究表明该光栅具有优异的耐受性和稳定性。因此，