標題: Omnidirectional, polarization-independent, ultra-broadband metamaterial perfect absorber using field-penetration and reflected-wave-cancellation
作者: Zhong, Yan Kai
Lai, Yi-Chun
Tu, Ming-Hsiang
Chen, Bo-Ruei
Fu, Sze Ming
Yu, Peichen
Lin, Albert
電子工程學系及電子研究所
光電工程學系
Department of Electronics Engineering and Institute of Electronics
Department of Photonics
公開日期: 16-五月-2016
摘要: In this work, we present the result of nickel (Ni)-based metamaterial perfect absorbers (MPA) with ultra-broadband close-to-one absorbance. The experimental broadband characteristic is significantly improved over the past effort on metamaterial perfect absorbers. An indepth physical picture and quantitative analysis is presented to reveal the physical origin of its ultrabroadband nature. The key constituent is the cancellation of the reflected wave using ultra-thin, moderate-extinction metallic films. The ultra-thin metal thickness can reduce the reflection as the optical field penetrates through the metallic films. This leads to minimal reflection at each ultra-thin metal layer, and light is penetrating into the Ni/SiO2 stacking. More intuitively, when the layer thickness is much smaller than the photon wavelength, the layer is essentially invisible to the photons. This results in absorption in the metal thin-film through penetration while there is minimal reflection by the metal film. More importantly, the experimental evidence for omni-directionality and polarization-insensitivity are established for the proposed design. Detailed measurement is conducted. Due to the ultrathin metal layers and the satisfactory tolerance in dielectric thickness, the broadband absorption has minimal degradation at oblique incidence. Such a wide angle, polarization-insensitive, ultra-broadband MPA can be very promising in the future, and the optical physics using sub-skin-depth metal film can also facilitate miniaturized high-performance nano-photonic devices. (C) 2016 Optical Society of America.
URI: http://dx.doi.org/10.1364/OE.24.00A832
http://hdl.handle.net/11536/133772
ISSN: 1094-4087
DOI: 10.1364/OE.24.00A832
期刊: OPTICS EXPRESS
Volume: 24
Issue: 10
顯示於類別:期刊論文