Optimization and photomodification of extremely broadband optical response of plasmonic core-shell obscurants

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:484

Article

de Silva, Vashista C.^1,2  Nyga, Piotr³  Drachev, Vladimir P.^1,2,4 

[1] Univ North Texas, Dept Phys & Adv Mat, 1155 Union Circle, Denton, TX 76203 USA

[2] Univ North Texas, Mfg Inst, 1155 Union Circle, Denton, TX 76203 USA

[3] Mil Univ Technol, Inst Optoelect, 2 Kaliskiego Str, PL-00908 Warsaw, Poland

[4] Skolkovo Inst Sci & Technol, 3 Nobel St, Moscow 143026, Russia

关键词: Broadband absorption;    Nanoparticle;    Nobel metal;    Silica;    Mass extinction coefficient;    Photomodification;    Plasmonic;    Core-shell;    Obscurants;   

DOI  :  10.1016/j.jcis.2016.08.044

来源: Elsevier

【 摘 要 】

Plasmonic resonances of the metallic shells depend on their nanostructure and geometry of the core, which can be optimized for the broadband extinction normalized by mass. The fractal nanostructures can provide a broadband extinction. It allows as well for a laser photoburning of holes in the extinction spectra and consequently windows of transparency in a controlled manner. The studied core-shell microparticles synthesized using colloidal chemistry consist of gold fractal nanostructures grown on precipitated calcium carbonate (PCC) microparticles or silica (SiO2) microspheres. The optimization includes different core sizes and shapes, and shell nanostructures. It shows that the rich surface of the PCC flakes is the best core for the fractal shells providing the highest mass normalized extinction over the extremely broad spectral range. The mass normalized extinction cross section up to 3 m(2)/g has been demonstrated in the broad spectral range from the visible to mid-infrared. Essentially, the broadband response is a characteristic feature of each core-shell microparticle in contrast to a combination of several structures resonant at different wavelengths, for example nanorods with different aspect ratios. The photomodification at an IR wavelength makes the window of transparency at the longer wavelength side. (C) 2016 Elsevier Inc. All rights reserved.

【 授权许可】

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