Perera, S.Fickenscher, M. A.Jackson, H. E.Smith, L. M.Yarrison-Rice, J. M.Joyce, H. J.Gao, Q.Jagadish, C.Zhang, X.Zou, J.Tan, Hark Hoe2015-10-212015-10-210003-6951http://hdl.handle.net/1885/16000CW and time-resolvedphotoluminescence measurements are used to investigate exciton recombination dynamics in GaAs∕AlGaAsheterostructurenanowires grown with a recently developed technique which minimizes twinning. A thin capping layer is deposited to eliminate the possibility of oxidation of the AlGaAs shell as a source of oxygen defects in the GaAs core. We observe exciton lifetimes of ∼1ns, comparable to high quality two-dimensional double heterostructures. These GaAsnanowires allow one to observe state filling and many-body effects resulting from the increased carrier densities accessible with pulsed laser excitation.S.P., M.A.F., H.E.J., L.M.S., and J.M.Y.-R. acknowledge the financial support of the University of Cincinnati and the National Science Foundation through Grant Nos. EEC/NUE- 0532495, ECCS-0701703, and DMR/MWN-0806700. H.J.J., Q.G., H.H.T., C.J., X.Z., and J.Z. acknowledge support from the Australian Research Council and the Australian National Fabrication Facility.3 pageshttp://www.sherpa.ac.uk/romeo/issn/0003-6951..."Publishers version/PDF may be used on author's personal website, institutional website or institutional repository" from SHERPA/RoMEO site (as at 21/10/15). Copyright 2008 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters and may be found at https://doi.org/10.1063/1.2967877Keywords: Crystals; Electric wire; Excitons; Gallium alloys; Heterojunctions; Laser excitation; Oxygen; Pulsed laser applications; Semiconducting gallium; Carrier densities; Core-shell nanowires; Double heterostructures; Exciton lifetimes; Exciton recombinations; G2008-08-0610.1063/1.29678772015-12-08