February 27, 2009: Mikael Rechtsman, CIMS
Upper bounds on photonic
bandgaps
A 20year search has been on to find photonic crystals (periodic
dielectric structures) with the largest
possible full photonic bandgaps. A large, robust bandgap is key
to the many applications of these materials,
which include nearlossless waveguiding, optical filtering,
optical computing, and others. A number
of threedimensional structures with large gaps have been
proposed (e.g., a diamond lattice of spheres,
the "Woodpile" structure), and in two dimensions, structural
optimizations to find the largestbandgap
structure have been performed. So far, however, there has been
no work on
finding rigorous limits on how high the bandgap may be. In
this talk, I present upper bounds on the
bandgaps of two and threedimensional photonic crystals.
