title: Controlling the emission profile of a nanowire with a conical taper.
abstract: The influence of a tapering on nanowire light-emission profiles is studied. We show that, for nanowires with divergent output beams, the introduction of a conical tapering with a small opening angle reduces the beam divergence and increases transmission. This results in a dramatic increase in the collection efficiency of the detection optics. For a realistic tapering and a modest NA, the collection efficiency is enhanced by more than a factor of 2. This improvement is ensured by the adiabatic expansion of the guided mode in the tapering.
authors.affiliation: Department of Photonics Engineering, DTU Fotonik, Technical University of Denmark, Building 343, DK-2800 Kongens Lyngby, Denmark. ngre@fotonik.dtu.dk
authors.forename: Niels
authors.initials: N
authors.lastname: Gregersen
authors.forename: Torben R
authors.initials: TR
authors.lastname: Nielsen
authors.forename: Julien
authors.initials: J
authors.lastname: Claudon
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Gérard
authors.forename: Jesper
authors.initials: J
authors.lastname: Mørk