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arXiv · 0707.3113

Excitons in Silicon Nanocrystalites: The Nature of Luminescence

Eleonora Luppi·Federico Iori·Rita Magri·Olivia Pulci·Stefano Ossicini·Elena Degoli·Valerio Olevano
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Abstract

The absorption and emission spectra of silicon nanocrystals up to 1 nm diameter including geometry optimization and the many-body effects induced by the creation of an electron-hole pair have been calculated within a first-principles framework. Starting from hydrogenated silicon clusters of different size, different Si/O bonding at the cluster surface have been considered. We found that the presence of a Si-O-Si bridge bond originates significative excitonic luminescence features in the visible range that are in fair agreement with the experimental outcomes.

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Eleonora Luppi, Federico Iori, Rita Magri, Olivia Pulci, Stefano Ossicini, Elena Degoli, Valerio Olevano. 2007-07-20. Excitons in Silicon Nanocrystalites: The Nature of Luminescence. https://doi.org/10.1103/physrevb.75.033303

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