Optical investigation of GaAs/AlGaAs heterostructure nanowires

ORAL

Abstract

A set of GaAs/AlGaAs heterosturcture nanowires which contain quantum well tubes (QWTs) with AlGaAs layers on both sides wrapped around a 50nm GaAs core are grown by Au-seeded MOCVD. Individual nanowires are studied by low temperature photoluminescence (PL) experiments, which give evidence of increasing quantum confinement with decreased QW growth time. Using structural and alloy concentration information obtained from high resolution transmission electron microscope measurements, we are able to carry out an eigenfunction expansion calculation using a cylindrical QW. By employing this theoretical modeling, we can calculate the QW widths from the ground state emission of these QWTs. A linear relationship between the QW growth time and QW width is found. Localized quantum dots in very narrow GaAs QWTs are also observed. In addition, spatially-resolved PL measurements show that these localized states are randomly distributed along the long axis of the nanowire.

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Authors

  • Teng Shi

    University of Cincinnati

  • Howard Jackson

    University of Cincinnati

  • Leigh Smith

    University of Cincinnati, Department of Physics, University of Cincinnati, Ohio 45221-0011, USA

  • Jan Yarrison-Rice

    Miami University, Department of Physics, Miami University, Oxford, Ohio 45056, USA

  • Bryan Wong

    Sandia National Laboratories

  • Nian Jiang

    Australian National University

  • Qiang Gao

    Australian National University, Department of Electronic and Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian

  • Hoe Tan

    Australian National University

  • Chennupati Jagadish

    Australian National University, Department of Electronic and Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian

  • Joanne Etheridge

    Monash University