Tight-binding calculations of the optical response of optimally P-doped Si nanocrystals : a model for localized surface plasmon resonance
Résumé
We present tight-binding calculations in the random-phase approximation of the optical response of Silicon nanocrystals (Si NCs) ideally doped with large concentrations of phosphorus (P) atoms. A collective response of P-induced electrons is demonstrated, leading to localized surface plasmon resonance (LSPR) when a Si NC contains more than ≈ 10 P atoms. The LSPR energy varies not only with doping concentration but also with NC size due to size-dependent screening by valence electrons. The simple Drude-like behavior is recovered for NC size above 4 nm. Si NCs containing a large number of deep defects in place of hydrogenic impurities do not give rise to LSPR.
Domaines
Matière Condensée [cond-mat]Origine | Fichiers éditeurs autorisés sur une archive ouverte |
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