2D photonic crystal
A scanning electron micrograph of the semiconductor (GaInAsP) 2D photonic-crystal slab, which has a triangular lattice structure with an
air hole radius of 0.29a (lattice constant a = 300 to 500 nm) and a thickness of 245 nm. A
5-nm-wide single quantum well is inserted at the centre
of the slab to form the light-emitting layer (image and text: Science 308 1296).