Effects Of Defect Permittivity On Resonant Frequency And Mode Shape In The Three-Dimensional Woodpile Photonic Crystal

Tuning the resonant frequency of a 1 uc defect across the bandgap of a three-dimensional woodpile photonic crystal (PC) was achieved by altering the defect's permittivity. Experiments were performed at microwave frequencies and calculations were made using the transfer-scattering matrix method. Defect permittivity was varied by using solid materials of different permittivities or by constructing structures smaller than a lattice constant from the the PC lattice materials. These small structures, which will be referred to as "sublattice defects," produce an effective permittivity between their two materials' permittivities. Changes in mode shape with resonant frequency and permittivity were also examined.