Photonic dispersions of semiconductor-quantum-dot-array-based photonic crystals in primitive and face-centered cubic lattices

We study the energy dispersions of photonic crystals based on the semicondu ctor-quantum-dot arrays. It has been shown that for the most commonly used semiconductor materials, and as compared with the primitive cubic lattice, the photonic crystal in a face-centered cubic (fcc) lattice exhibits a very promising energy dispersion relationship with an overall photonic bandgap. The bandgap is most prominent along the Lambda (Gamma-L) line in q space. The results explain the difficulties in fabricating photonic crystals in fe e lattices. They explain also the experimental works of Vlasov et al. [Phys ical Review B55, R13357-13360 (1997)], where it has been demonstrated that for CdS nanocrystals embedded in fee porous silica matrices the photonic ba ndgaps are observed for any direction of the radiation incidence, being mos t pronounced for the [111] direction. (C) 2000 Academic Press.