Photonic crystals as host material for a new generation of microwave components
In order to verify simulations of a concave lens based upon a photonic crystal, it was scaled and built for the application in the microwave range. Its field distribution was measured between 5.5 and 12 GHz. Due to the effective refractive index smaller than 1, focusing points were found in spite of the concave shape. The survey of the field distributions at the investigated frequencies leads to other possible applications of photonic crystals in the microwave and millimetre wave region, like beam-splitter and prism.