Phonon-assisted recombination in Fe-based spin LEDs
Date
2006Author
Mallory, R.Yasar, M.
Itskos, Grigorios
Petrou, Athos Chariton
Kioseoglou, G.
Hanbicki, A. T.
Li, C. H.
Van't Erve, O. M. J.
Jonker, B. T.
Shen, M.
Saikin, S.
ISSN
1098-0121Source
Physical Review B - Condensed Matter and Materials PhysicsVolume
73Issue
11Google Scholar check
Metadata
Show full item recordAbstract
The electroluminescence (EL) spectra from Fe AlGaAs (n) GaAs AlGaAs (p) spin LEDs contain an e1 h1 excitonic feature in addition, they exhibit new features not present in the photoluminescence (PL) spectra, that are "satellites" or "replicas" of the exciton. These satellites are red shifted with respect to e1 h1 by energies that are approximately equal to those of zone edge phonons in GaAs. The intensity of the replicas depends strongly on bias voltage. In the presence of a magnetic field the satellites become circularly polarized as σ+ but their polarization is always lower than that of e1 h1. The satellites are interpreted as due to recombination processes that involve zone edge electrons that tunnel into the GaAs quantum well. These processes occur simultaneously with the emission of zone-edge phonons. Our interpretation is supported by a numerical simulation of the properties of electrons tunneling through an Fe GaAs (n) Schottky barrier. © 2006 The American Physical Society.