Fabrication of a 2D photonic bandgap by a holographic method

The authors present the realisation of a 2D photonic bandgap in gallium arsenide, with a holographic lithography technique. The photonic crystal consists of circular etched air holes on a triangular lattice, and has been obtained with the holographic recording of only three plane waves in a photoresist. The quality of the final structure shows that holographic lithography, which is a low cost method compared with electron beam lithography, has high potential for photonic microstructure fabrication.