Sturmberg Björn C P, Dossou Kokou B, Botten Lindsay C, Asatryan Ara A, Poulton Christopher G, de Sterke C Martijn, McPhedran Ross C
1CUDOS and IPOS, School of Physics, University of Sydney, Australia.
Opt Express. 2011 Sep 12;19 Suppl 5:A1067-81. doi: 10.1364/OE.19.0A1067.
We analyze the absorption of solar radiation by silicon nanowire arrays, which are being considered for photovoltaic applications. These structures have been shown to have enhanced absorption compared with thin films, however the mechanism responsible for this is not understood. Using a new, semi-analytic model, we show that the enhanced absorption can be attributed to a few modes of the array, which couple well to incident light, overlap well with the nanowires, and exhibit strong Fabry-Pérot resonances. For some wavelengths the absorption is further enhanced by slow light effects. We study the evolution of these modes with wavelength to explain the various features of the absorption spectra, focusing first on a dilute array at normal incidence, before generalizing to a dense array and off-normal angles of incidence. The understanding developed will allow for optimization of simple SiNW arrays, as well as the development of more advanced designs.
我们分析了用于光伏应用的硅纳米线阵列对太阳辐射的吸收情况。与薄膜相比，这些结构已被证明具有增强的吸收能力，然而其背后的机制尚不清楚。通过使用一种新的半解析模型，我们表明增强的吸收可归因于阵列的几种模式，这些模式与入射光耦合良好，与纳米线重叠良好，并表现出强烈的法布里 - 珀罗共振。对于某些波长，慢光效应会进一步增强吸收。我们研究这些模式随波长的演变，以解释吸收光谱的各种特征，首先关注垂直入射时的稀疏阵列，然后推广到密集阵列和非垂直入射角的情况。所形成的理解将有助于优化简单的硅纳米线阵列，以及开发更先进的设计。
