Growth and characterization of wurtzite GaP nanowires with control over axial and radial growth by use of HCl in-situ etching

We report on the synthesis of non-tapered wurtzite (WZ) GaP nanowires by use of in-situ etching and the structural and optical characterization thereof. HCl was evaluated as an in-situ etchant in order to impede the onset of radial growth since the WZ crystal phase in GaP nanowires preferentially grows at relatively high growth temperatures around 600 °C, at which strong radial growth typically occurs. Transmission electron microscopy measurements confirmed non-tapered WZ GaP nanowires after growth. Photoluminescence characterization revealed defect related red emission, possibly related to transitions within the bandgap. Raman measurements show that the phonon energies in WZ GaP are very close in energy to the phonon energies in zinc blende GaP.