title: Impact of Coulomb scattering on the ultrafast gain recovery in InGaAs quantum dots.
abstract: The application of quantum dot (QD) semiconductor optical amplifiers (SOAs) in above 100-Gbit Ethernet networks demands an ultrafast gain recovery on time scales similar to that of the input pulse approximately 100 GHz repetition frequency. Microscopic scattering processes have to act at shortest possible time scales and mechanisms speeding up the Coulomb scattering have to be explored, controlled, and exploited. We present a microscopic description of the gain recovery by coupled polarization- and population dynamics in a thermal nonequilibrium situation going beyond rate-equation models and discuss the limitations of Coulomb scattering between 0D and 2D-confined quantum states. An experiment is designed which demonstrates the control of gain recovery for THz pulse trains in InGaAs QD-based SOAs under powerful electrical injection.
authors.affiliation: Institut für Optik und Atomare Physik, Technische Universität Berlin, 10623 Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Gomis-Bresco
authors.forename: S
authors.initials: S
authors.lastname: Dommers
authors.forename: V V
authors.initials: VV
authors.lastname: Temnov
authors.forename: U
authors.initials: U
authors.lastname: Woggon
authors.forename: M
authors.initials: M
authors.lastname: Laemmlin
authors.forename: D
authors.initials: D
authors.lastname: Bimberg
authors.forename: E
authors.initials: E
authors.lastname: Malic
authors.forename: M
authors.initials: M
authors.lastname: Richter
authors.forename: E
authors.initials: E
authors.lastname: Schöll
authors.forename: A
authors.initials: A
authors.lastname: Knorr