Crystal Design Tosses Out the Woodpile

Three-dimensional photonic crystals have shown tremendous promise in the development of all-optical devices for telecommunications and computing, but thus far their deployment has been hamstrung by their innate complexity. A new design presented by a University of Toronto team in the May 11 issue of Science, however, may usher in the mass production of photonic bandgap crystals.

Rather than the typical woodpile structure of alternating, spaced stacks of material, the researchers' crystal is chiral, with square spiral posts on a tetragonal lattice. They say that the crystal, which displays a 24 percent bandgap of the center frequency in the inverted variant, could be mass-produced using glancing-angle deposition in a one-step process.