Fabrication and Characterization of GaAs/AlGaAs Core-Shell Photonic Nanowires

Abstract

GaAs/AlGaAs core-shell nanowires (NWs) were grown on GaAs(111)B substrates by Au-assisted molecular beam epitaxy (MBE) to investigate how different Al compositions in the shell influences the structural and optical properties of the NWs. Investigations with a secondary electron microscope (SEM) revealed that an increase in Al content leads to an increase in radial growth rate and a decrease in the axial growth rate of the AlGaAs shell. Low temperature μ-photoluminescence (PL) measurements showed that there was great improvement in the luminescence for the GaAs/AlGaAs core-shell NWs compared to GaAs NWs without shell.