Optical properties of metallo-dielectric microspheres in opal structures

Abstract

We report the fabrication of opal structure using metallo-dielectric silica microspheres. Mono-dispersed silica microspheres were coated with silver using an electrode-less wet-plating technique. Thin slabs of opal were obtained by assembling the silver-coated microspheres between two glass plates using a forced-packing method. The optical properties of the resulting opal structure were studied in the infrared range. Good agreement is obtained with the predictions of a multiple scattering approach, provided that the silver layer is modelled as a silver composite.

Chemical Aspects of Three-Dimensional Photonic Crystals

“…Metallic PCs have attracted great attention in recent years due to the potential for new properties and phenomena, including tailored thermal emission, localized surface plasmonic resonance (LSPR), , as well as PBG properties at IR wavelengths . Gold and silver inverse opals have been formed by electroplating the silica particles, followed by colloidal assembly via sedimentation. Yu et al have prepared Ni inverse opals and showed the thermal emission properties …”

Hybrid Colloidal Plasmonic‐Photonic Crystals

“…[ 30 − 32 ] However, in spite of the variety of techniques used for core-shell preparation, [ 33 , 34 ] the intriguing optical properties of nanoshell PhCs became strongly obscured [ 35 ] by the strong absorption occurring due to imperfections of thin metal coatings on highly curved surfaces of nanospheres. [ 36 ] The nanoshells of inverted topology consisting of a small metal core surrounded by a massive dielectric shell were also considered as building blocks of colloidal crystals [ 37 , 38 ] that are capable of opening the omnidirectional PBG. [ 39 ] However, in contrast to expectations, the refl ectance of such crystals was merely the response of similar crystals assembled from all-dielectric beads, whereas the localized plasmons just added the absorption-related band to opal transmission.…”

Fabrication and optical characterization of gold-infiltrated silica opals

“…To fabricate the opal needed for infiltration, we used a force packing method that was successfully employed in fabricating large scale multilayered opals [9,10]. The details of the packing method have been reported already for larger particles [10]. Figure 1 shows a schematic diagram for the force packing method.…”