Sun Mengdi, Huang Di, Golvari Pooria, Kuebler Stephen M, Delfyett Peter J, Kik Pieter G
Bradley Department of Electrical and Computer Engineering, Virginia Tech, Arlington, 22203, VA, USA.
CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, 32816, FL, USA.
Nanophotonics. 2023 Aug 3;12(18):3545-3552. doi: 10.1515/nanoph-2023-0205. eCollection 2023 Sep.
A light-trapping transparent electrode design based on sub-surface binary dielectric gratings is introduced and demonstrated experimentally. The structure consists of metallic wires patterned with an array of silicon nanobeams. Optimization of the grating geometry achieves selective suppression of zero-order diffraction, while enabling redirection of incident light to an angle that exceeds critical angle of the local environment. Subsequent total-internal reflection allows recovery of light initially incident on the patterned metal wire. Experiments involving amorphous silicon gratings patterned on gold wires demonstrate a light-trapping efficiency exceeding 41 %. Modeling of crystalline silicon nanobeams on silver wires suggests that a shadowing loss reduction of 82 % is feasible. The achievement of a large shadowing reduction using a coplanar structure with high manufacturing tolerance and a polarization-insensitive optical response makes this design a promising candidate for integration in a wide range of real-world photonic devices.
介绍了一种基于亚表面二元介质光栅的光捕获透明电极设计，并进行了实验验证。该结构由带有硅纳米束阵列图案的金属线组成。通过优化光栅几何结构，可以选择性地抑制零阶衍射，同时使入射光重定向到超过局部环境临界角的角度。随后的全内反射使得最初入射到图案化金属线上的光得以恢复。在金线表面图案化非晶硅光栅的实验表明，光捕获效率超过41%。在银线上对晶体硅纳米束进行建模表明，将阴影损失降低82%是可行的。使用具有高制造容差的共面结构和对偏振不敏感的光学响应实现大幅阴影减少，使得该设计成为集成到广泛实际光子器件中的有前景的候选方案。
