Optical demonstration of a crystal band structure formation

The optical modes of chains of coupled micron sized semiconductor cavities have been studied using photoluminescence spectroscopy and detailed calcula tions. With an increasing number of cavities, the chains exhibit photon ban d gaps at several Brillouin zone boundaries. The sizes of the band Sops are shown to depend on the coupling between the microcavities and also on the order of the Brillouin zone involved.