Premium
Light‐Induced Color Change in the Sapphirinid Copepods: Tunable Photonic Crystals
Author(s) -
Gur Dvir,
Leshem Ben,
Farstey Viviana,
Oron Dan,
Addadi Lia,
Weiner Steve
Publication year - 2016
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.201504339
Subject(s) - structural coloration , materials science , wavelength , photonic crystal , photonics , visible spectrum , iridescence , optoelectronics , microscopy , optics , reflectivity , blue light , optical microscope , scanning electron microscope , physics , composite material
Light‐induced tunable photonic systems are rare in nature, and generally beyond the state‐of‐the‐art in artificial systems. Sapphirinid male copepods produce some of the most spectacular colors in nature. The male coloration, used for communication purposes, is structural and is produced from ordered layers of guanine crystals separated by cytoplasm. It is generally accepted that the colors of the males are related to their location in the epipelagic zone. By combining correlative reflectance and cryoelectron microscopy image analyses, together with optical time lapse recording and transfer matrix modeling, it is shown that male sapphirinids have the remarkable ability to change their reflectance spectrum in response to changes in the light conditions. It is also shown that this color change is achieved by a change in the thickness of the cytoplasm layers that separate the guanine crystals. This change is reversible, and is both intensity and wavelength dependent. This capability provides the male with the ability to efficiently reflect light under certain conditions, while remaining transparent and hence camouflaged under other conditions. These copepods can thus provide inspiration for producing synthetic tunable photonic arrays.