The Electron-Hole Interactions in Si Hydrogenate Nanocrystals: Tight-Binding Theory

Abstract:

Theory of electronic and optical properties of excitonic states confining in Si nanocrystals is presented. The electron and hole states are numerically computed using the atomistic empirical tight-binding Hamiltonian including the spin-orbit coupling together with the first nearest-neighboring interaction. We theoretically study the electron-hole interactions in spherical silicon hydrogenated nanocrystals by incorporating coulomb and exchange interaction into the empirical tight-binding model. The comparisons of coulomb and exchange energies with empirical pseudopotential method (EPM), tight-binding method (TB), effective-mass approximation (EMA) and ab initio calculations are quantitatively realized. Finally the energies of the excitonic ground states obtained from diagonalizing the tight-binding configuration-interaction scheme are in a good agreement with other theoretical and experimental data.

• Periodical: Advanced Materials Research (Volume 1131)
• Pages: 110-116
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1131.110
• Online since: December 2015
• Authors: Worasak Sukkabot*
• Keywords: Coulomb, Exchange Interaction, Nanocrystal, Silicon, Tight-Binding Calculations

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