Superconducting photonic crystals
  The band structure of a novel type of photonic crystal with superconducting constituent elements is calculated numerically via a plane wave expansion. The density of states and the dependence of the width of the photonic gap on the filling factor is analyzed for a two-dimensional photonic crystal consisting of an infinite array of parallel superconducting cylinders. 
Oleg L. Berman, Yurii E. Lozovik, Sergey L. Eiderman and Rob D.   Coalson