Biological glass fibers: Correlation between optical and structural properties
Open Access
- 9 March 2004
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 101 (10), 3358-3363
- https://doi.org/10.1073/pnas.0307843101
Abstract
Biological systems have, through the course of time, evolved unique solutions for complex optical problems. These solutions are often achieved through a sophisticated control of fine structural features. Here we present a detailed study of the optical properties of basalia spicules from the glass sponge Euplectella aspergillum and reconcile them with structural characteristics. We show these biosilica fibers to have a distinctive layered design with specific compositional variations in the glass/organic composite and a corresponding nonuniform refractive index profile with a high-index core and a low-index cladding. The spicules can function as single-mode, few-mode, or multimode fibers, with spines serving as illumination points along the spicule shaft. The presence of a lens-like structure at the end of the fiber increases its light-collecting efficiency. Although free-space coupling experiments emphasize the similarity of these spicules to commercial optical fibers, the absence of any birefringence, the presence of technologically inaccessible dopants in the fibers, and their improved mechanical properties highlight the advantages of the low-temperature synthesis used by biology to construct these remarkable structures.Keywords
This publication has 37 references indexed in Scilit:
- Phylogeny of the family Spongicolidae (Crustacea: Stenopodidea): evolutionary trend from shallow-water free-living to deep-water sponge-associated habitatJournal of the Marine Biological Association of the United Kingdom, 2003
- Coexistence of Amorphous and Crystalline Calcium Carbonate in Skeletal TissuesConnective Tissue Research, 2003
- Rigid Biological Composite Materials: Structural Examples for Biomimetic DesignExperimental Mechanics, 2002
- Vision in hydrothermal vent shrimpPhilosophical Transactions Of The Royal Society B-Biological Sciences, 2000
- Variations in ambient light emission from black smokers and flange pools on the Juan De Fuca RidgeGeophysical Research Letters, 2000
- Siliceous spicules of Tethya seychellensis (Porifera) support the growth of a green alga: a possible light conducting systemMarine Ecology Progress Series, 1994
- A simple way to make tough ceramicsNature, 1990
- Thermal stress measurements in optical-fibre preforms using preform-profiling techniquesElectronics Letters, 1984
- Studies on hexactinellid sponges. III. The taxonomic status of hexactinellida within the poriferaPhilosophical Transactions of the Royal Society of London. B, Biological Sciences, 1983
- Mechanism of Internal Stratification of Siliceous Sponge SpiculesNature, 1971