Supercontinuum Generation in Naturally Occurring Glass Sponges Spicules

Abstract

The complex process of supercontinuum generation (SG) is known to be exploitable for designing spatially coherent white light sources emitting light simultaneously in the ultraviolet, visible, and infrared ranges. Herein the first natural material able to generate in laboratory conditions a supercontinuum similar to those known from man-made photonic crystal fibers is described. The ability resides in siliceous 20-50 cm long spicules of the glass sponge Sericolophus hawaiicus. By shedding into the spicules optical peak intensities ranging from 1 to 100 TW cm(-2) the generation of a SG is revealed. The SG involves wavelengths between 650 and 900 nm and shows a maximum spectral spread for excitation at a wavelength of 750 nm. It is hypothesized that the SG is favored by spicules being a biocomposite that incorporates together isotopically pure biogenic silica (delta(30) Si = -3.28) and 15.2 +/- 1.3 mu g N -acetyl-glucosamine (chitin) per mg of silica. The internal organization of these spicules is distinguished by a solid silica core with a 1 mu m wide axial channel as well as a highly ordered silica-chitin composite. Such a composition and organization pattern may be of potential interest for the design of low temperature synthesis of future materials for light guidance

Lamellar architectures in stiff biomaterials may not always be templates for enhancing toughness in composites

“…Images of spicules from other Hexactinellid species that are partially dissolved in alkali solution reveal that the silica layers also contain a fibrillar organic matrix similar to the interlayers [21][22][23] . Thus, this organic matrix serves both as a scaffold within the layers and a glue between them 24 .…”

Hexactinellida from the Perth Canyon, Eastern Indian Ocean, with descriptions of five new species

“…They create complex physical structures, are long lived and slow growing, and may act as nursery areas for motile organisms (Hogg et al 2010). They are of interest to material scientists because of optical and structural properties of their skeletons (Wang et al 2011, Ehrlich et al 2016), and are model organisms for the study of conduction systems in early Metazoan evolution, as they lack a nervous system but are capable of impulse conduction (Leys et al 2007).…”

Optical Properties of Nanostructured Silica Structures From Marine Organisms

“…Such spicules were assumed to act as a natural supercontinuum generator that involves wavelengths between 650 and 900 nm and a maximum spectral propagation at λ = 750 nm. This optical property was assumed to be due to its bio-composite nature combining mineral biosilica and organic matrix, including chitin (Ehrlich et al, 2016).…”