1204.0421 (Prokop Hapala et al.)

Optical properties and band structure of 3nm Si nanocrystals    [PDF]

Prokop Hapala, Pavel Jelinek

Silicon nanocrystals of up to 3nm size were studied using density functional theory (DFT) to obtain insight into dependence of its luminescence properties on surface passivation and geometric distortion. Luminescence properties are discussed from point of view of both - real space and momentum space structure of molecular orbitals. According to our best knowledge this is the first time, when comprehensive study of band structure of realistic nanocrystal is given including full geometric and electronic relaxation with the surface passivation groups. We conclude that band structure in nanocrystals of this size is in many case crucial, however strong perturbation by polarized surface groups and geometric distortion could lead to consid- erable moderation of momentum space selection rules.

View original: http://arxiv.org/abs/1204.0421