title: Two-photon injection of polaritons in semiconductor microstructures.
abstract: We experimentally demonstrate that two-photon pumping of "dark" excitons in quantum wells embedded in semiconductor microcavities can result in exciton-polariton injection and photon lasing. In the case of a semiconductor micropillar pumped at half of the exciton frequency, we observe a clear threshold behavior, characteristic of the vertical cavity surface emitting laser transition. These results are interpreted in terms of stimulated emission of terahertz photons, which allows for conversion of "dark" excitons into exciton-polaritons.
authors.forename: Godefroy
authors.initials: G
authors.lastname: Leménager
authors.forename: Ferruccio
authors.initials: F
authors.lastname: Pisanello
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Bloch
authors.forename: Alexey
authors.initials: A
authors.lastname: Kavokin
authors.forename: Alberto
authors.initials: A
authors.lastname: Amo
authors.forename: Aristide
authors.initials: A
authors.lastname: Lemaitre
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Galopin
authors.forename: Isabelle
authors.initials: I
authors.lastname: Sagnes
authors.forename: Massimo
authors.initials: M
authors.lastname: De Vittorio
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Giacobino
authors.forename: Alberto
authors.initials: A
authors.lastname: Bramati
mesh_terms: D007834:Lasers; D049449:Luminescence; D017785:Photons; D012666:Semiconductors; D013997:Time Factors