Space charge mediated negative di erential resistance in terhertz quantum well detectors
Résumé
In THz Quantum Well Infrared Photodetectors, a built-in-charge-mediated regime transition of the electronic transport is thoroughly investigated. The very strong current discontinuity and neg- ative di erential resistivity behavior are explained in terms of band structure reorganizations. The analysis of bias versus current measurements reveals that the transition occurs when the rst two wells of the structure become partially drained, and that second well enters the ionized regime before the rst one. Both many body e ects and a careful model of the contact have to be considered to account for these features. The probable source of the built-in charge is identi ed as Intersubband Impact Ionization, of which this regime transition would be one of the few experimental evidence, and provide an original approach to investigate hot electrons kinetics in these structures.
Fichier principal
2011_-_Delga_et_al._J._Appl._Phys._110_013714_author_version_.pdf (2.07 Mo)
Télécharger le fichier
Origine | Fichiers produits par l'(les) auteur(s) |
---|
Loading...