title: Strained GaAs/InGaAs Core-Shell Nanowires for Photovoltaic Applications.
abstract: We report on the successful growth of strained core-shell GaAs/InGaAs nanowires on Si (111) substrates by molecular beam epitaxy. The as-grown nanowires have a density in the order of 10(8) cm(-2), length between 3 and 3.5 μm, and diameter between 60 and 160 nm, depending on the shell growth duration. By applying a range of characterization techniques, we conclude that the In incorporation in the nanowires is on average significantly smaller than what is nominally expected based on two-dimensional growth calibrations and exhibits a gradient along the nanowire axis. On the other hand, the observation of sharp dot-like emission features in the micro-photoluminescence spectra of single nanowires in the 900-1000-nm spectral range highlights the co-existence of In-rich enclosures with In content locally exceeding 30 %.
authors.affiliation: Department of Materials Science and Technology, University of Crete, P.O. Box 2208, 70013, Heraklion, Greece.
authors.forename: K
authors.initials: K
authors.lastname: Moratis
authors.affiliation: CEA, INAC, 17 rue des Martyrs, 38054, Grenoble cedex 9, France.|Université Grenoble Alpes, F-38000, Grenoble, France.
authors.forename: S L
authors.initials: SL
authors.lastname: Tan
authors.affiliation: Department of Materials Science and Technology, University of Crete, P.O. Box 2208, 70013, Heraklion, Greece.|Microelectronics Research Group, IESL-FORTH, P.O. Box 1385, 71110, Heraklion, Greece.
authors.forename: S
authors.initials: S
authors.lastname: Germanis
authors.affiliation: Department of Materials Science and Technology, University of Crete, P.O. Box 2208, 70013, Heraklion, Greece.
authors.forename: C
authors.initials: C
authors.lastname: Katsidis
authors.affiliation: Microelectronics Research Group, IESL-FORTH, P.O. Box 1385, 71110, Heraklion, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Androulidaki
authors.affiliation: Microelectronics Research Group, IESL-FORTH, P.O. Box 1385, 71110, Heraklion, Greece.
authors.forename: K
authors.initials: K
authors.lastname: Tsagaraki
authors.affiliation: Microelectronics Research Group, IESL-FORTH, P.O. Box 1385, 71110, Heraklion, Greece.|Department of Physics, University of Crete, P.O. Box 2208, 70013, Heraklion, Greece.
authors.forename: Z
authors.initials: Z
authors.lastname: Hatzopoulos
authors.affiliation: Université Grenoble Alpes, F-38000, Grenoble, France.|CNRS, Institut NEEL, F-38000, Grenoble, France.
authors.forename: F
authors.initials: F
authors.lastname: Donatini
authors.affiliation: Université Grenoble Alpes, F-38000, Grenoble, France.|CNRS, Institut NEEL, F-38000, Grenoble, France.
authors.forename: J
authors.initials: J
authors.lastname: Cibert
authors.affiliation: CEA, INAC, 17 rue des Martyrs, 38054, Grenoble cedex 9, France.
authors.forename: Y-M
authors.initials: YM
authors.lastname: Niquet
authors.affiliation: Université Grenoble Alpes, F-38000, Grenoble, France.|CNRS, Institut NEEL, F-38000, Grenoble, France.
authors.forename: H
authors.initials: H
authors.lastname: Mariette
authors.affiliation: Department of Materials Science and Technology, University of Crete, P.O. Box 2208, 70013, Heraklion, Greece. pelekano@materials.uoc.gr.|CEA, INAC, 17 rue des Martyrs, 38054, Grenoble cedex 9, France. pelekano@materials.uoc.gr.|Université Grenoble Alpes, F-38000, Grenoble, France. pelekano@materials.uoc.gr.|Microelectronics Research Group, IESL-FORTH, P.O. Box 1385, 71110, Heraklion, Greece. pelekano@materials.uoc.gr.
authors.forename: N T
authors.initials: NT
authors.lastname: Pelekanos
keywords: Cathodoluminescence; Core-shell GaAs/InGaAs nanowires; Micro-Raman; Micro-photoluminescence; Nanostructure characterization; Photoluminescence