Photonic crystal type nanoarchitectures in butterfly wing scales

Abstract

Photonic crystals also called Photonic Band Gap (PBG) materials — are periodic dielectric composite structures, which affect the propagation of the light. These materials are intensively studied since two decades [1, 2], because of perspectives of their applications in optical devices, textiles and colorants. The diversity of photonic crystal type nanoarchitectures found in Nature is also in the focus of researchers’ attention. Living organisms, during millennia of evolution, achieved very complex and highly optimized micro- and nanostructures not only for interaction with visible light but also for other specified functions as for example UV protection, thermal regulation or adhesion. A very remarkable attribute is that these nanostructures are produced by a limited range of materials, which offers only a moderate refractive index contrast (1/1.6). The investigation of natural nanostructures leads to the knowledge that can be applied in the design of artificial biomimetic materials with photonic properties and can reduce the engineering effort in designing these materials and costs of their fabrication.