Photonic Band Gap in the Triangular Lattice of BEC vortices

We investigate the photonic bands of an atomic Bose-Einstein condensate with a triangular vortex lattice. Index contrast between the vortex cores and the bulk of the condensate is achieved through the enhancement of the index via atomic coherence. Frequency dependent dielectric function is used in the calculations of the bands, resulting in photonic band gap widths of a few MHz.