García de Arquer F Pelayo, Beck Fiona J, Konstantatos Gerasimos
ICFO – Institut de Ciènces Fotòniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain.
Opt Express. 2011 Oct 10;19(21):21038-49. doi: 10.1364/OE.19.021038.
We present a full wave 3D simulation study of optical absorption enhancement in solution processed metal-semiconductor nanocomposite ultrathin films, which consist of colloidal metallic nanoparticles (MNPs) and semiconductor matrices of polymer and colloidal quantum dots (CQD). We present an approach for modeling the optical properties of a CQD film, and study the effect of the optical properties of the semiconductor in the near field enhancement showing that CQD is a very promising platform to exploit the benefits of the near-field effects. We show that over a 100% enhancement can be achieved in the visible-near infrared region of the spectrum for CQD PbS films, with a maximum gain factor of 4 when MNPs are on resonance. We study in detail the effect of MNP capping for different ligand lengths and materials and propose solutions to optimize absorption enhancement.
我们展示了对溶液处理的金属-半导体纳米复合超薄膜中光吸收增强的全波三维模拟研究，该超薄膜由胶体金属纳米颗粒（MNP）以及聚合物和胶体量子点（CQD）的半导体基质组成。我们提出了一种对CQD薄膜光学性质进行建模的方法，并研究了半导体光学性质在近场增强中的作用，表明CQD是利用近场效应优势的非常有前景的平台。我们表明，对于CQD PbS薄膜，在光谱的可见-近红外区域可实现超过100%的增强，当MNP处于共振时，最大增益因子为4。我们详细研究了不同配体长度和材料的MNP封端的影响，并提出了优化吸收增强的解决方案。
