Excitons in Si1-xGex nanocrystals : Ab initio calculations
作者： E. L. de Oliveira , E. L. Albuquerque , J. S. de Sousa , G. A. Farias
DOI: 10.1063/1.2913314
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摘要: The electronic structure of hydrogen-passivated Si1−xGex nanocrystals is investigated by means ab initio calculations. Our calculated optical gaps and electron-hole binding energies decrease linearly with x, while the exciton exchange energy increases x due to increase spatial extent electron hole wave functions. This also functions overlap, leading recombination lifetimes that are very sensitive Ge content. results exhibited good agreement available theoretical data.
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