A 20-year 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 near-lossless waveguiding, optical
filtering, optical computing, and others. A number of three-dimensional
structures with large gaps have been proposed (e.g., a diamond lattice
of spheres,[1] the "Woodpile" structure [2]), and in two dimensions,
structural optimizations to find the largest-bandgap structure have
been performed, (e.g., in refs. [3-4]). 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 one- and
two-dimensional photonic crystals.
References
- Phys. Rev. Lett. 65, 3152 (1990)
- J. Mod. Opt. 41, 231 (1994)
- Appl. Phys. B. 81, 235 (2005)
- Phys. Rev. Lett. 101, 073902 (2008)
|
