Chen Ke, Wu Rui, Zheng Hongmei, Zhang Guojun, Wang Yuanyuan, Wang Haishuo, Chen Shunhua
J Opt Soc Am A Opt Image Sci Vis. 2019 Apr 1;36(4):647-654. doi: 10.1364/JOSAA.36.000647.
We theoretically introduce a concept of two-dimensional super-quadratic subwavelength gratings (2D SQSWGs) to further investigate how geometrical shape influences the reflection behavior for biomimetic moth-eye structures, and the outline shape can be controlled by changing the degree of the grating's profile function. Numerical studies on the reflection behavior of the 2D SQSWGs and nanorod gratings reveal that the parabola-shaped grating (degree n=2) with a nearly linear graded index profile has superior antireflection performance, and its average weighted reflectivity (R) is as low as 0.99% under AM1.5 solar illumination. Moreover, research results indicate that the 2D nanocone gratings (n=1) have the best angle-independent optical property. The research findings can be used to guide the design of photovoltaic cells based on biomimetic moth-eye structures, and the concept of 2D SQSWGs can be potentially applied to other photovoltaic and optical devices.
我们从理论上引入了二维超二次亚波长光栅（2D SQSWGs）的概念，以进一步研究几何形状如何影响仿生蛾眼结构的反射行为，并且轮廓形状可以通过改变光栅轮廓函数的程度来控制。对2D SQSWGs和纳米棒光栅反射行为的数值研究表明，具有近似线性渐变折射率分布的抛物线形光栅（n = 2度）具有优异的抗反射性能，在AM1.5太阳光照下其平均加权反射率（R）低至0.99%。此外，研究结果表明，二维纳米锥光栅（n = 1）具有最佳的角度无关光学特性。这些研究结果可用于指导基于仿生蛾眼结构的光伏电池设计，并且二维超二次亚波长光栅的概念可能应用于其他光伏和光学器件。
