Unraveling electronic band structure of narrow-bandgap p-n nanojunctions in heterostructured nanowires.

The electronic band structure of complex nanostructured semiconductors has a considerable effect on the final electronic and optical properties of the material and, ultimately, on the functionality of the devices incorporating them. Valence electron energy-loss spectroscopy (VEELS) in the transmission electron microscope (TEM) provides the possibility of measuring this property of semiconductors with high spatial resolution. However, it still represents a challenge for narrow-bandgap semiconductors, since an electron beam with low energy spread is required.

Sb Incorporation in Wurtzite and Zinc Blende InAs Sb Branches on InAs Template Nanowires.

The physical properties of material largely depend on their crystal structure. Nanowire growth is an important method for attaining metastable crystal structures in III-V semiconductors, giving access to advantageous electronic and surface properties. Antimonides are an exception, as growing metastable wurtzite structure has proven to be challenging.

Direct nucleation, morphology and compositional tuning of InAs Sb nanowires on InAs (111) B substrates.

III-V ternary nanowires are interesting due to the possibility of modulating their physical and material properties by tuning their material composition. Amongst them InAs Sb nanowires are good candidates for applications such as Infrared detectors. However, this material has not been grown directly from substrates, in a large range of material compositions.

Selective GaSb radial growth on crystal phase engineered InAs nanowires.

In this work we have developed InAs nanowire templates, with designed zinc blende and wurtzite segments, for selective growth of radial GaSb heterostructures using metal organic vapor phase epitaxy. We find that the radial growth rate of GaSb is determined by the crystal phase of InAs, and that growth is suppressed on InAs segments with a pure wurtzite crystal phase. The morphology and the thickness of the grown shell can be tuned with full control by the growth conditions.