We show that ominidirectional reflection is not a sufficient signature of a photonic bandgap. Although dramatic angular redistribution takes place, the mode density of the electromagnetic field is hardly altered within the ominidirectional reflection range but rather has characteristics typical of a waveguide. The strikingly large polarization anisotropy is due to the huge dielectric contrast but not to a photonic bandgap.
© 2000 Optical Society of America
Christa Hooijer, Daan Lenstra, and Ad Lagendijk, "Mode density inside an omnidirectional mirror is heavily directional but not small," Opt. Lett. 25, 1666-1668 (2000)