Luminescence polarization of silicon nanocrystals
Type de document :
Compte-rendu et recension critique d'ouvrage
Titre :
Luminescence polarization of silicon nanocrystals
Auteur(s) :
Allan, Guy [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Delerue, Christophe [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Niquet, Yann-Michel [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Delerue, Christophe [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Niquet, Yann-Michel [Auteur]
Titre de la revue :
Physical Review B: Condensed Matter and Materials Physics (1998-2015)
Pagination :
205301/1-8
Éditeur :
American Physical Society
Date de publication :
2001
ISSN :
1098-0121
Discipline(s) HAL :
Sciences de l'ingénieur [physics]
Résumé en anglais : [en]
We consider theoretically the polarization of the luminescence of Si nanocrystals that arises from the anisotropy of the optical moments. No-phonon and phonon-assisted optical transitions are calculated in tight binding ...
Lire la suite >We consider theoretically the polarization of the luminescence of Si nanocrystals that arises from the anisotropy of the optical moments. No-phonon and phonon-assisted optical transitions are calculated in tight binding and interpreted using effective-mass theory. In contrast to direct-gap semiconductors, we show that simple selection rules cannot be established in Si nanocrystals because the degree of linear polarization presents large oscillations with respect to the size of the clusters. This effect is due to the indirect nature of the Si band gap that leads to a dependence of the optical matrix elements on the oscillatory overlaps between electron and hole states in momentum space. However, in a statistical ensemble of crystallites elongated in a given direction and with size larger than 2–3 nm, we obtain that the light is in average polarized along this direction, in agreement with the experiments.Lire moins >
Lire la suite >We consider theoretically the polarization of the luminescence of Si nanocrystals that arises from the anisotropy of the optical moments. No-phonon and phonon-assisted optical transitions are calculated in tight binding and interpreted using effective-mass theory. In contrast to direct-gap semiconductors, we show that simple selection rules cannot be established in Si nanocrystals because the degree of linear polarization presents large oscillations with respect to the size of the clusters. This effect is due to the indirect nature of the Si band gap that leads to a dependence of the optical matrix elements on the oscillatory overlaps between electron and hole states in momentum space. However, in a statistical ensemble of crystallites elongated in a given direction and with size larger than 2–3 nm, we obtain that the light is in average polarized along this direction, in agreement with the experiments.Lire moins >
Langue :
Anglais
Vulgarisation :
Non
Source :