title: Many-body and correlation effects on parametric polariton amplification in semiconductor microcavities.
abstract: The complexity induced by the Coulomb interaction between electrons determines the noninstantaneous character of exciton-exciton collisions. We show that the exciton-photon coupling in semiconductor microcavities is able to alter the exciton dynamics during collisions strongly affecting the effective scattering rates. Our analysis clarifies the origin of the great enhancement of parametric gain observed when increasing the polariton splitting. It also demonstrates that exciton-exciton collisions in semiconductors can be controlled and engineered to produce almost decoherence-free collisions for the realization of all-optical microscopic devices.
authors.affiliation: Istituto Nazionale per la Fisica della Materia INFM and Dipartimento di Fisica della Materia e Tecnologie Fisiche Avanzate, Universit à di Messina, Salita Sperone 31, I-98166 Messina, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Savasta
authors.forename: Omar
authors.initials: O
authors.lastname: Di Stefano
authors.forename: Raffaello
authors.initials: R
authors.lastname: Girlanda