Reflections on iridescent neck and breast feathers of the peacock, Pavo cristatus

Abstract

The blue neck and breast feathers of the peacock are structurally coloured due to an intricate photonic crystal structure in the barbules consisting of a two-dimensionally ordered rectangular lattice of melanosomes (melanin rodlets) and air channels embedded in a keratin matrix. We here investigate the feather coloration by performing microspectrophotometry, imaging scatterometry and angle-dependent reflectance measurements. Using previously determined wavelength-dependent refractive indices of melanin and keratin, we interpret the spectral and spatial reflection characteristics by comparing the measured spectra to calculated spectra by effective-medium multilayer and full three-dimensional finite-difference time-domain modelling. Both modelling methods yield similar reflectance spectra indicating that simple multilayer modelling is adequate for a direct understanding of the brilliant coloration of peacock feathers.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 14, 2018
Source ID
10.1098/rsfs.2018.0043

Entities

People

  • Bodo D. Wilts
  • Doekele G Stavenga
  • Pascal Freyer

Organizations

  • Air Force Office of Scientific Research
  • University of Fribourg
  • University of Groningen

Tags

Fields of Study

  • Physics

Readers

  • Chemistry (specifically Chemical Fluorescence)
  • Materials Science and Engineering.
  • Nanofabrication and Microfabrication.