title: Localization-dependent photoluminescence spectrum of biexcitons in semiconductor quantum wires.
abstract: We study exciton and biexciton spectra in disordered semiconductor quantum wires by means of nanophotoluminescence spectroscopy. We demonstrate a close link between the exciton localization length along the wire and the occurrence of a biexciton spectral line. The biexciton signature appears only if the corresponding exciton state extends over more than a few tens of nanometers. We also measure a nonmonotonous variation of the biexciton binding energy with decreasing exciton localization length. This behavior is quantitatively well reproduced by the solution of the single-band Schrödinger equation of the four-particle problem in a one-dimensional confining potential.
authors.affiliation: Institut de Photonique et d'Electronique Quantiques, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Feltrin
authors.forename: F
authors.initials: F
authors.lastname: Michelini
authors.forename: J L
authors.initials: JL
authors.lastname: Staehli
authors.forename: B
authors.initials: B
authors.lastname: Deveaud
authors.forename: V
authors.initials: V
authors.lastname: Savona
authors.forename: J
authors.initials: J
authors.lastname: Toquant
authors.forename: X L
authors.initials: XL
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Ogura