Institute for Advanced Materials (IAM), School of Physics and Telecommunication Engineering, South China Normal University, Higher Education Mega Center, Guangzhou 510006, China.
Nano Lett. 2012 Jan 11;12(1):440-5. doi: 10.1021/nl203763k. Epub 2011 Dec 23.
We show that a planar structure, consisting of an ultrathin semiconducting layer topped with a solid nanoscopically perforated metallic film and then a dielectric interference film, can highly absorb (superabsorb) electromagnetic radiation in the entire visible range, and thus can become a platform for high-efficiency solar cells. The perforated metallic film and the ultrathin absorber in this broadband superabsorber form a metamaterial effective film, which negatively refracts light in this broad frequency range. Our quantitative simulations confirm that the superabsorption bandwidth is maximized at the checkerboard pattern of the perforations. These simulations show also that the energy conversion efficiency of a single-junction amorphous silicon solar cell based on our optimized structure can exceed 12%.
我们展示了一种平面结构，它由一个超薄的半导体层构成，顶部覆盖着一个固体纳米穿孔金属膜，然后是一个介电干涉膜，这种结构可以在整个可见光谱范围内高度吸收（超吸收）电磁辐射，因此可以成为高效太阳能电池的平台。穿孔金属膜和超薄吸收器在这个宽带超吸收器中形成一个等效的负折射材料，在这个宽频范围内对光产生负折射。我们的定量模拟证实，超吸收带宽在穿孔的棋盘图案中达到最大值。这些模拟还表明，基于我们优化结构的单结非晶硅太阳能电池的能量转换效率可以超过 12%。
