Kim Hyeonwoo, Kwak Hojae, Jung Incheol, Kim Mi Suk, Kim Jeonghyun, Park Hui Joon, Lee Kyu-Tae
Opt Express. 2021 Oct 25;29(22):35366-35376. doi: 10.1364/OE.440989.
Arrays of high-index dielectric nanoparticles supporting both electrical and magnetic resonances have gained increasing attention for their excellent light-trapping (LT) effects, thus greatly improving the performance of ultrathin solar cells. This work explores front-located, high-index dielectric subwavelength nanosphere arrays as an efficient and broadband LT structure patterned on top of an ultrathin perovskite solar cell (PSC) for a greatly enhanced absorption. Combined strong light scattering and anti-reflection properties achieved by optimized geometrical parameters of the LT structure lead to a broadband absorption enhancement in the ultrathin thickness of a photoactive layer (100 nm) yielding the short-circuit current density (Jsc) of 18.7 mA/cm, which is 31.7% higher than that of a planar counterpart. Moreover, effects of the LT structure on far-field radiation patterns, scattering cross-sections, multipoles' contributions, and asymmetry parameters along with the incidence angle and polarization dependence are investigated. The present strategy could be applied to diverse applications, such as other ultrathin or semitransparent solar cells, absorbers and photodetectors.
支持电谐振和磁谐振的高折射率介电纳米颗粒阵列因其出色的光捕获（LT）效应而受到越来越多的关注，从而极大地提高了超薄太阳能电池的性能。这项工作探索了位于超薄钙钛矿太阳能电池（PSC）顶部的前侧高折射率介电亚波长纳米球阵列，作为一种高效的宽带LT结构，用于大幅增强吸收。通过优化LT结构的几何参数实现的强光散射和抗反射特性相结合，导致光活性层超薄厚度（100 nm）内的宽带吸收增强，产生了18.7 mA/cm的短路电流密度（Jsc），比平面同类产品高31.7%。此外，还研究了LT结构对远场辐射方向图、散射截面、多极贡献以及不对称参数的影响，以及入射角和偏振依赖性。本策略可应用于多种应用，如其他超薄或半透明太阳能电池、吸收器和光电探测器。
