School of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.
College of Physics and Communication Electronics, Jiangxi Normal University, Nanchang 330022, China.
Sci Rep. 2017 Mar 3;7:43803. doi: 10.1038/srep43803.
Recently, techniques involving random patterns have made it possible to control the light trapping of microstructures over broad spectral and angular ranges, which provides a powerful approach for photon management in energy efficiency technologies. Here, we demonstrate a simple method to create a wideband near-unity light absorber by introducing a dense and random pattern of metal-capped monodispersed dielectric microspheres onto an opaque metal film; the absorber works due to the excitation of multiple optical and plasmonic resonant modes. To further expand the absorption bandwidth, two different-sized metal-capped dielectric microspheres were integrated into a densely packed monolayer on a metal back-reflector. This proposed ultra-broadband plasmonic-photonic super absorber demonstrates desirable optical trapping in dielectric region and slight dispersion over a large incident angle range. Without any effort to strictly control the spatial arrangement of the resonant elements, our absorber, which is based on a simple self-assembly process, has the critical merits of high reproducibility and scalability and represents a viable strategy for efficient energy technologies.
最近，涉及随机图案的技术使得在宽光谱和角度范围内控制微结构的光捕获成为可能，这为提高能效技术中的光子管理能力提供了一种强大的方法。在这里，我们通过在不透明金属膜上引入密集且随机的金属覆盖单分散介电微球图案，展示了一种制造宽带近全光吸收体的简单方法；由于激发了多种光学和等离子体共振模式，该吸收体得以工作。为了进一步扩展吸收带宽，我们将两种不同尺寸的金属覆盖介电微球集成到金属背反射器上的密集单层中。这种所提出的超宽带等离子体-光子超吸收体在介电区域表现出理想的光捕获性能，并且在大入射角范围内具有轻微的色散。我们的吸收体基于简单的自组装过程，无需严格控制共振元件的空间排列，具有高重现性和可扩展性的关键优点，代表了高效能源技术的一种可行策略。
