Investigation of a Multi-Layer Absorber Exhibiting the Broadband and High Absorptivity in Red Light and Near-Infrared Region

Guoxiang Peng; Wei-Zheng Li; Ling-Chieh Tseng; Cheng-Fu Yang

doi:10.3390/nano13040766

Investigation of a Multi-Layer Absorber Exhibiting the Broadband and High Absorptivity in Red Light and Near-Infrared Region

Nanomaterials (Basel). 2023 Feb 18;13(4):766. doi: 10.3390/nano13040766.

Authors

Guoxiang Peng¹, Wei-Zheng Li², Ling-Chieh Tseng², Cheng-Fu Yang^{2

3}

Affiliations

¹ School of Ocean Information Engineering, Jimei University, Xiamen 361021, China.
² Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 811, Taiwan.
³ Department of Aeronautical Engineering, Chaoyang University of Technology, Taichung 413, Taiwan.

Abstract

In this study, an absorber with the characteristics of high absorptivity and ultra-wideband (UWB), which was ranged from the visible light range and near-infrared band, was designed and numerically analyzed using COMSOL Multiphysics^® simulation software (version 6.0). The designed absorber was constructed by using two-layer square cubes stacked on the four-layer continuous plane films. The two-layer square cubes were titanium dioxide (TiO₂) and titanium (Ti) (from top to bottom) and the four-layer continuous plane films were Poly(N-isopropylacrylamide) (PNIPAAm), Ti, silica (SiO₂), and Ti. The analysis results showed that the first reason to cause the high absorptivity in UWB is the anti-reflection effect of top TiO₂ layer. The second reason is that the three different resonances, including localized surface plasmon resonance, the propagating surface plasmon resonance, and the Fabry-Perot (FP) cavity resonance, are coexisted in the absorption peaks of the designed absorber and at least two of them can be excited at the same time. The third reason is that two FP resonant cavities were formed in the PNIPAAm and SiO₂ dielectric layers. Because of the combination of the anti-reflection effect and the three different resonances, the designed absorber presented the properties of UWB and high absorptivity.

Keywords: COMSOL Multiphysics® software; Fabry-Perot cavity resonance; absorber; localized surface plasmon resonance; ultra-wideband.

Grants and funding

This research was supported by projects of Ministry of Science and Technology, Taiwan, under Nos. MOST 110-2622-E-390-002, MOST 110-2221-E-390-020, and MOST 111-2221-E-390-018.