Early-stage relaxation of hot electrons by LO phonon emission

Citation
H. Castella et Jw. Wilkins, Early-stage relaxation of hot electrons by LO phonon emission, PHYS REV B, 61(23), 2000, pp. 15827-15836
Citations number
43
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
0163-1829 → ACNP
Volume
61
Issue
23
Year of publication
2000
Pages
15827 - 15836
Database
ISI
SICI code
0163-1829(20000615)61:23<15827:EROHEB>2.0.ZU;2-U
Abstract
Ultrafast spectroscopy gives insight into the relaxation and dephasing of e lectrons during the first femtoseconds after an optical excitation. A theor etical description of this early-time regime requires a proper treatment of retardation effects for the different scattering processes. The scattering of electrons by optical phonons is investigated within the S-matrix formal ism. This perturbative scheme, equivalent to the non-equilibrium Green's fu nction technique of Kadanoff and Baym [Quantum Statistical Mechanics (Benja min, New York, 1962)], reproduces the phonon oscillations observed in four- wave mixing experiments on GaAs. The differential transmission spectrum, ho wever, shows a sharper phonon replica than in experiments where additional dephasing mechanisms such as electron correlation effects may further broad en the replica.