Photonic Structures for Coloration in the Biological World

Abstract

In the biological world the living organisms have exploited photonic structures to produce striking structural coloration since the Cambrian period. In recent years, structural colors and associated photonic structures have received increasing attention from scientists in a wide variety of disciplines ranging from physics, biology, and chemistry to material science. Revealed natural photonic structures are diverse, delicate, and multifunctional as well. Natural photonic structures and their ingenious ways of light steering could be a great source of inspiration, invaluable to our bio-inspired technologies. In this chapter, we will give a review on natural photonic structures and their coloration. A historical survey is given in Sect. 8.2. In Sect. 8.3, we discuss the mechanisms of structural coloration, including interference, diffraction, scattering, or their combination. Experimental and theoretical methods for studying natural photonic structures are briefly reviewed in Sect. 8.4. In Sect. 8.5, we present some typical photonic structures occurring in the biological world, such as thin films, multilayers, diffraction gratings, photonic crystals, and amorphous photonic structures, and also discuss their coloration mechanisms. An outlook is given in the last section.