Influence of Quantum Dot Morphology on the Optical Properties of GaSb/GaAs Multilayers

ORAL

Abstract

We examine the influence of quantum dot (QD) morphology on the optical properties of two-dimensional (2D) GaSb/GaAs multilayers, with and without three-dimensional nanostructures. Using nanostructure sizes from scanning transmission electron microscopy and local Sb compositions from local-electrode atom-probe tomography as input into self-consistent Schrodinger–Poisson simulations based on 8 x 8 kp theory, we compute confinement energies for GaSb QDs, circular arrangements of smaller QDs, termed QD-rings, and 2D layers on GaAs substrates. The computed confinement energies and the measured photoluminescence emission energies increase from QDs to QD-rings to 2Dlayers, enabling direct association of nanostructure morphologies with the optical properties of the GaSb/GaAs multilayers. This work opens opportunities for tailoring near to far infrared optoelectronic devices by varying the QD morphology.

*
NSF Grant DGE 1256260

–

Presenters

  • Christian Greenhill

    • Materials Science and Engineering, University of Michigan
    • Department of Materials Science & Engineering, University of Michigan
    • Department of Materials Science & Engineering, Northwestern University
    • University of Michigan

Authors

  • Christian Greenhill

    • Materials Science and Engineering, University of Michigan
    • Department of Materials Science & Engineering, University of Michigan
    • Department of Materials Science & Engineering, Northwestern University
    • University of Michigan

  • Alexander Chang

    • Department of Materials Science & Engineering, Northwestern University
    • Northwestern University

  • Eric Zech

    • Department of Materials Science & Engineering, University of Michigan

  • Stephen Clark

    • Department of Electrical and Computer Engineering, University of New Mexico

  • Ganesh Balakrishnan

    • Department of Electrical and Computer Engineering, University of New Mexico

  • Rachel Goldman

    • Materials Science and Engineering, University of Michigan
    • Department of Materials Science & Engineering, University of Michigan
    • Department of Materials Science and Engineering, University of Michigan
    • University of Michigan
    • Materials Science Engineering, University of Michigan