Wang Min, Hu Chenggang, Pu Mingbo, Huang Cheng, Zhao Zeyu, Feng Qin, Luo Xiangang
State Key Laboratory of Optical Technologies for Microfabrication, Institute of Optics and Electronics, Chinese Academy of Science, P.O.box 350, Chengdu 610209, China.
Opt Express. 2011 Oct 10;19(21):20642-9. doi: 10.1364/OE.19.020642.
Truncated spherical voids nanostructured tungsten films are shown to have nearly perfect absorption with characteristics of broad-band, polarization-independent and wide-incidence angle in near infrared and visible regime. Through optimizing material and structural parameters, we can achieve the absorbance above 90% from 420THz to 600THz within incidence angle from 0° to 60° for TE polarization and from 450THz to 800THz within incidence angle from 0° to 75° for TM polarization. In particular, absorbance can achieve 99.9% at 550.5THz for both polarizations under normal incidence. Such strong absorption is explained using multilayer effective media theory and cavity resonance.
截断球形空洞纳米结构钨薄膜在近红外和可见光区域表现出近乎完美的吸收特性，具有宽带、偏振无关和宽入射角的特点。通过优化材料和结构参数，对于TE偏振，在入射角从0°到60°范围内，我们可以在420THz至600THz实现吸光度高于90%；对于TM偏振，在入射角从0°到75°范围内，在450THz至800THz实现吸光度高于90%。特别地，在垂直入射时，两种偏振在550.5THz处的吸光度均可达到99.9%。利用多层有效介质理论和腔共振对这种强吸收进行了解释。
