inverse opals

Controlling the dynamics of spontaneous emission from quantum dots by photonic crystals
P. Lodahl, A. F. van Driel, I. S. Nikolaev, A. Irman, K. Overgaag, D. Vanmaekelbergh, and W. L. Vos
Nature 430, 654-657 (2004)

Inhibited light propagation and broad band reflection in photonic air-sphere crystals
M. S. Thijssen, R. Sprik, J. E. G. J. Wijnhoven, M. Megens, T. Narayanan, A. Lagendijk, and W. L. Vos
Phys. Rev. Lett. 83, 2730-2733 (1999)