title: Optical properties of diatom nanostructured biosilica in Arachnoidiscus sp: micro-optics from mother nature.
abstract: Some natural structures show three-dimensional morphologies on the micro- and nano-scale, characterized by levels of symmetry and complexity well far beyond those fabricated by best technologies available. This is the case of diatoms, unicellular microalgae, whose protoplasm is enclosed in a nanoporous microshell, made of hydrogenated amorphous silica, called frustule. We have studied the optical properties of Arachnoidiscus sp. single valves both in visible and ultraviolet range. We found photonic effects due to diffraction by ordered pattern of pores and slits, accordingly to an elaborated theoretical model. For the first time, we experimentally revealed spatial separation of focused light in different spots, which could be the basis of a micro-bio-spectrometer. Characterization of such intricate structures can be of great inspiration for photonic devices of next generation.
authors: Institute for Microelectronic and Microsystems, Department of Naples, National Research Council, Naples, Italy.
authors: Maria Antonietta
authors: MA
authors: Ferrara
authors: Institute for Microelectronic and Microsystems, Department of Naples, National Research Council, Naples, Italy.
authors: Principia
authors: P
authors: Dardano
authors: Institute for Microelectronic and Microsystems, Department of Naples, National Research Council, Naples, Italy.
authors: Luca
authors: L
authors: De Stefano
authors: Institute for Microelectronic and Microsystems, Department of Naples, National Research Council, Naples, Italy.
authors: Ilaria
authors: I
authors: Rea
authors: Institute for Microelectronic and Microsystems, Department of Naples, National Research Council, Naples, Italy.
authors: Giuseppe
authors: G
authors: Coppola
authors: Institute for Microelectronic and Microsystems, Department of Naples, National Research Council, Naples, Italy.
authors: Ivo
authors: I
authors: Rendina
authors: Laboratory of Biology of Algae, Department of Biology, University of Rome "Tor Vergata", Rome, Italy.
authors: Roberta
authors: R
authors: Congestri
authors: Department of Environmental, biological, and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy.
authors: Alessandra
authors: A
authors: Antonucci
authors: Department of Environmental, biological, and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy.
authors: Mario
authors: M
authors: De Stefano
authors: Institute for Microelectronic and Microsystems, Department of Naples, National Research Council, Naples, Italy.
authors: Edoardo
authors: E
authors: De Tommasi
mesh_terms: D017377:Diatoms / Q000648:ultrastructure*; D008027:Light; D049329:Nanostructures / Q000648:ultrastructure; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D012822:Silicon Dioxide