Department of Physics, University of South Florida, Tampa, 33620, USA.
Smart Materials Laboratory, Department of Applied Physics, Northwestern Polytechnical University, Xi'an, 710129, China.
Sci Rep. 2017 Sep 5;7(1):10569. doi: 10.1038/s41598-017-10520-w.
We demonstrate that the metamaterial perfect absorber behaves as a meta-cavity bounded between a resonant metasurface and a metallic thin-film reflector. The perfect absorption is achieved by the Fabry-Perot cavity resonance via multiple reflections between the "quasi-open" boundary of resonator and the "close" boundary of reflector. The characteristic features including angle independence, ultra-thin thickness and strong field localization can be well explained by this meta-cavity model. With this model, metamaterial perfect absorber can be redefined as a meta-cavity exhibiting high Q-factor, strong field enhancement and extremely high photonic density of states, thereby promising novel applications for high performance sensor, infrared photodetector and cavity quantum electrodynamics devices.
我们证明了超材料完美吸收体表现为一个由共振超表面和金属薄膜反射器构成的亚波长金属腔。通过在“准开放”谐振腔边界和“封闭”反射器边界之间的多次反射，实现了 Fabry-Perot 腔共振的完美吸收。角度无关性、超薄厚度和强场局域化等特性可以通过这个亚波长金属腔模型得到很好的解释。通过这个模型，可以将超材料完美吸收体重新定义为一个具有高 Q 值、强场增强和极高光子态密度的亚波长金属腔，从而为高性能传感器、红外探测器和腔量子电动力学器件的应用提供了新的前景。
