Coupling of plasmon and 3D antireflection quasi-photonic crystal structure for enhancement infrared absorption
In this study, the carbon-matrix Ag wing with a hierarchical sub-micron antireflection quasi-photonic crystal structure (HSAS) was fabricated by a simple and promising method. This method combines chemosynthesis with biomimetic techniques, without the requirement of expensive equipment and energy intensive processes. Here, the Troides helena (Linnaeus) (T. helena) forewing (T_FW) was chosen as the biomimetic template. The carbon-matrix Ag butterfly wing (Ag@C_T_FW) achieves a drastically enhanced infrared absorption over a broad spectral range, especially, over the near infrared region. Here, we report methods to enhance and modify the plasmonic resonances in such structures by strongly coupling plasmonic resonances to HSAS. Using the finite difference time domain (FDTD) method, the absorption spectra and the distribution of the energy density near the Ag NPs surface were simulated. Based on the experiment and simulation results, these findings demonstrate that the enhanced infrared absorption over a broad spectral range is due to the mechanism that the plasmon and the coherent coupling between adjacent resonance systems integrate with the HSAS.