Strong anti-Stokes photoluminescence of GaAs free excitons in GaAs/Ga1-xAlxAs heterojunctions - art. no. 195321

Citation
Jx. Shen et al., Strong anti-Stokes photoluminescence of GaAs free excitons in GaAs/Ga1-xAlxAs heterojunctions - art. no. 195321, PHYS REV B, 6419(19), 2001, pp. 5321
Citations number
17
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
0163-1829 → ACNP
Volume
6419
Issue
19
Year of publication
2001
Database
ISI
SICI code
0163-1829(20011115)6419:19<5321:SAPOGF>2.0.ZU;2-O
Abstract
In heterojunctions, the strong electric field present at the interface driv es the carriers vertically and therefore opens the way to several unique fe atures observed in the optical spectra and transport experiments. In this w ork, we report the observation of GaAs free-exciton luminescence by excitin g GaAs/Ga1-xAlxAs heterojunctions below the energy of the free excitons in GaAs. This anti-Stokes photoluminescence has a long rise time and decay tim e. We attribute the anti-Stokes photoluminescence to the recombination of t he excitons formed bimolecularly from free carriers excited from ionized do nor and acceptor levels. This mechanism is enabled by the bending of the ba nd structure across the heterointerface and yields the emission of photons at energies above the injected photons.