Structural color in the Swallow Tanager (Tersina viridis): using the Korringa-Kohn-Rostoker method to simulate disorder in natural photonic crystals

INCHAUSSANDAGUE, M.; D'AMBROSIO, C.; BARREIRA, A.; SKIGIN, D.; TUBARO, P.

PHYSICAL REVIEW E - STATISTICAL PHYSICS, PLASMAS, FLUIDS AND RELATED INTERDISCIPLINARY TOPICS

American Physical Society

Lugar: New York; Año: 2018 vol. 98

1063-651X

The plumage of birds often exhibits attractive color effects produced by the interaction of light with thephotonic microstructure present in the feather barbs and barbules. This microstructure constitutes a naturalphotonic crystal that rejects radiation of wavelengths contained within the band gap, which significantly alters theobserved coloration depending on the incidence conditions. In spite of the high degree of regularity exhibited bythe barb?s microstructure of many species, the disorder present in these natural photonic crystals might modifythe reflected response. In this paper, we address the problem of modeling the electromagnetic response of aquasiordered photonic structure, using an electromagnetic method only suitable for strictly periodic structures.In particular, we simulate the reflected response of the plumage of the Swallow Tanager (Tersina viridis) bytwo different approaches. On the one hand, we compute the reflected response by averaging reflectance spectracalculated by the Korringa-Kohn-Rostoker method for different geometrical parameters. We also apply the innerextinction approximation, which represents imperfections in the structure by adding a small imaginary part tothe dielectric constant of the inclusions. The agreement between the experimental and the simulated resultsevidences the potential of the proposed methods to reproduce the electromagnetic response of natural photonicstructures.