Origin of the excitonic recombinations in hexagonal boron nitride by spatially resolved cathodoluminescence spectroscopy

Périne Jaffrennou (1, 2, 3) , Julien Barjon (4) , Jean‐sébastien Lauret (3) , Brigitte Attal-Trétout (2) , François Ducastelle (1) , Annick Loiseau (1)

1 LEM - ONERA - CNRS - Laboratoire d'étude des microstructures [Châtillon]
2 ONERA - The French Aerospace Lab [Châtillon]
3 LPQM - Laboratoire de Photonique Quantique et Moléculaire
4 GEMAC - Groupe d'Etude de la Matière Condensée

The excitonic recombinations in hexagonal boron nitride (hBN) are investigated with spatially resolved cathodoluminescence spectroscopy in the UV range. Cathodoluminescence images of an individual hBN crystallite reveals that the 215 nm free excitonic line is quite homogeneously emitted along the crystallite whereas the 220 nm and 227 nm excitonic emissions are located in specific regions of the crystallite. Transmission electron microscopy images show that these regions contain a high density of crystalline defects. This suggests that both the 220 nm and 227 nm emissions are produced by the recombination of excitons bound to structural defects.

Mots clés: excitons; Boron nitride nanotubes; cathodoluminescence; excitons.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Périne Jaffrennou, Julien Barjon, Jean‐sébastien Lauret, Brigitte Attal-Trétout, François Ducastelle, et al.. Origin of the excitonic recombinations in hexagonal boron nitride by spatially resolved cathodoluminescence spectroscopy. 2007. ⟨hal-00159913⟩