Tuning birefringence by using two-dimensional photonic band structure

Birefringence is an optical characteristic intrinsic to anisotropic materials. In the paper, we show the microwave birefringence can be tuned as a function of frequency by utilizing the band structures of a two-dimensional photonic crystal consisting of metallic cylinders arranged in a two-dimensional square lattice. By measuring the transmission and mapping the field inside of the sample, the birefringence was directly determined. An agreement between band structure calculations and experiment measurements was achieved, with the frequency at the center of transmission band showing the least birefringence and the frequency at the band edge exhibiting the most. (C) 2009 American Institute of Physics. [doi:10.1063/1.3247584]