Diffraction in crystalline colloidal-array photonic crystals.

We characterized the diffraction and crystal structure of a crystalline colloidal array (CCA) photonic crystal composed of 270 nm diameter polystyrene spheres which have a nearest neighbor spacing of approximately 540 nm. This CCA diffracts light in first order at approximately 1200 nm and shows strong diffraction in the visible spectral region from higher order planes. We quantitatively examined the relative diffraction intensities of the putative fcc (111), (200), (220), and (311) planes.