The University of Utah has discovered a natural photonic crystal with an "ideal" structure, it claims.

"It appears that a simple creature like a beetle provides us with one of the technologically most sought-after structures for the next generation of computing," said scientist Michael Bartl. "Nature has simple ways of making structures and materials that are still unobtainable with our million-dollar instruments and engineering strategies."

The beetle, Lamprocyphus Augustus, has a green iridescence which comes from sub-micron tetrahedral structures on its surface.

"When made from an appropriate material, a diamond-like structure would create a large photonic bandgap, meaning the crystalline structure prevents the propagation of light of a certain range of wavelengths," said the University. "Materials with such bandgaps are necessary if researchers are to engineer optical circuits that can manipulate visible light."

Individual 200x100µm scales on the exoskeleton of the beetle Lamprocyphus Augustus appearing green because the fingernail-like material in the scales has a diamond-like crystal structure that reflects green light.

The team is now trying to copy the structure in a semiconducting material to make a controllable optical element.

Made of fingernail-like chitin, the natural crystals are not stable, semiconducting, or effective enough for use as they are, so Bartl and team are trying to design a synthetic version using scale material as a mould to make the crystals from a transparent semiconductor.

Researchers are seeking photonic crystals to manipulate photons in light-based computers.

"You would be able to solve certain problems that we are not able to solve now," said Bartl. "For certain problems, an optical computer could do in seconds what regular computers need years for."

Curiosity was aroused in the beetle because its iridescence is unusual.

25mm long, this insect from Brazil grows tetrahedral structure photonic crystals, a task that has so far stymied human researchers. " Such a structure is considered an ideal architecture for photonic crystals", said the University of Utah

"Many iridescent objects appear that way only when viewed at certain angles, but the beetle remains iridescent from any angle," said Utah.

It transpires that a single beetle scale is not a continuous crystal, but includes some 200 pieces of chitin, each with the diamond-like structure but each oriented a different direction. So each piece reflects a slightly different wavelength or shade of green.

"Each piece is too small to be seen individually by your eye, so what you see is a composite effect," with the beetle appearing green from any angle, said Bartl.