Butterfly Callophris rubi with gyroid structure and weevil Entimus imperialis with diamond structure

The cuticular microstructure in the wing scales of various butterfly (Papilionidae and Lycaenidae) and weevil species can be modelled by a gyroid and diamond structure, respectively.

Optical measurements

  • The structure of the wing scales is investigated by scanning electron microscopy (SEM) and by transmission electron microscopy (TEM).
  • The far-field angular distribution of the light scattered from single domains on single scales is visualized with an imaging scatterometer.
  • Transmittance and reflectance spectra from single scales are measured with a microspectrophotometer.

Computer simulations

  • The cubic air–cuticle structures of the scales are modelled by structures based on the level surfaces.
  • Light scattering from the cubic air-cuticle structures is calculated by means of TDME3D, a massively parallel three-dimensional finite-difference finite-domain (FDTD) Maxwell solver. One calculation (one wavelength, one angle of incidence and one type of polarization) requires a memory of approximately 260 GB (approx. equal to 1.5 X 109 lattice points).
  • Photonic band structure diagrams for the cubic-air structures are calculated with the MIT photonics bandgap package
Selected publications:
  • B.D. Wilts, K. Michielsen, H. De Raedt, and D.G. Stavenga,
    "Iridescence and spectral filtering of the gyroid photonic crystals in Parides sesostris wing scales",
    Interface Focus 2, 681 – 687 (2012)
  • B. Wilts, K. Michielsen, H. De Raedt, and D. Stavenga,
    "Fotonische kristallen in kevers en vlinders",
    Nederlands Tijdschrift voor Natuurkunde 78, 264 - 267 (2012)
  • B.D. Wilts, K. Michielsen, H. De Raedt, and D.G. Stavenga,
    "Hemispherical Brillouin zone imaging of a diamond-type bio-photonic crystal",
    J. R. Soc. Interface 9, 1609 - 1614 (2012)
  • B.D. Wilts, K. Michielsen, J. Kuipers, H. De Raedt, and D.G. Stavenga,
    "Brilliant camouflage: Photonic crystals in the Diamond Weevil, Entimus imperialis",
    Proc. R. Soc. B 279, 2524 – 2530 (2012)
  • K. Michielsen, H. De Raedt, and D. Stavenga
    "Reflectivity of the gyroid biophotonic crystals in the ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi",
    J. R. Soc. Lond. Interface 7, 765 - 771 (2010)
  • K.F.L. Michielsen and J.S. Kole,
    "Photonic band gaps in materials with triply periodic surfaces and related tubular structures",
    Phys. Rev. B 68, 115107 (2003)