Gap Maps for Triangular Photonic Crystals with a Dispersive and Absorbing Component
2005 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 72, no 20, 205120- p.Article in journal (Refereed) Published
Some consequences of a strong lattice resonance in the working frequency region of a 2D photonic crystal are investigated. It opens for two kinds of gaps in the dispersion relations: structure gaps and a polaritonic gap. A transverse optical oscillator model for ceramic beryllium oxide has been used to simulate the dielectric function of the polaritonic medium. The effective index of refraction is different on either side of the resonance, which causes BeO to act both as a high index material and a low index material. Gap maps for two kinds of triangular structures were calculated: BeO cylinders in air or in a high-index, nondispersive dielectric. These gap maps show appearance and disappearance of the transverse electric, transverse magnetic, and complete structure gaps as function of the packing fraction r/a, and the lattice constant a. The results illustrate the importance of whether the dielectric or the polaritonic material has the higher effective dielectric function. The effects of absorption, included by the damping parameter of the oscillator model, are briefly discussed.
Place, publisher, year, edition, pages
2005. Vol. 72, no 20, 205120- p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-93207DOI: 10.1103/PhysRevB.72.205120OAI: oai:DiVA.org:uu-93207DiVA: diva2:166616