title: Wurtzite GaAs/AlGaAs core-shell nanowires grown by molecular beam epitaxy.
abstract: We report the growth of GaAs/AlGaAs core-shell nanowires (NWs) on GaAs(111)B substrates by Au-assisted molecular beam epitaxy. Electron microscopy shows the formation of a wurtzite AlGaAs shell structure both in the radial and the axial directions outside a wurtzite GaAs core. With higher Al content, a lower axial and a higher radial growth rate of the AlGaAs shell were observed. Room temperature and low temperature (4.4 K) micro-photoluminescence measurements show a much higher radiative efficiency from the GaAs core after the NW is overgrown with a radial AlGaAs shell.
authors.affiliation: Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway. hailong.zhou@iet.ntnu.no
authors.forename: H L
authors.initials: HL
authors.lastname: Zhou
authors.forename: T B
authors.initials: TB
authors.lastname: Hoang
authors.forename: D L
authors.initials: DL
authors.lastname: Dheeraj
authors.forename: A T J
authors.initials: AT
authors.lastname: van Helvoort
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.forename: J C
authors.initials: JC
authors.lastname: Harmand
authors.forename: B O
authors.initials: BO
authors.lastname: Fimland
authors.forename: H
authors.initials: H
authors.lastname: Weman
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D001152:Arsenicals / Q000737:chemistry*; D005708:Gallium / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D036103:Nanotechnology / Q000379:methods*; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D001152:Arsenicals; C043055:gallium arsenide; D005708:Gallium; D000535:Aluminum