Role of defect saturation in improving optical response from InGaN nanowires in higher wavelength regime.

Growth of InGaN, having high Indium composition without compromising crystal quality has always been a great challenge to obtain efficient optical devices. In this work, we extensively study the impact of non-radiative defects on optical response of the plasma assisted molecular beam epitaxy (PA-MBE) grown InGaN nanowires, emitting in the higher wavelength regime ([Formula: see text] nm). Our analysis focuses into the effect of defect saturation on the optical output, manifested by photoluminescence (PL) spectroscopy.

Triaxially uniform high-quality Al GaN (x ∼ 50%) nanowires on template free sapphire substrate.

We have demonstrated the growth of high-quality Al GaN (x ∼ 50%) nanowires (NWs) for the first time on the sapphire substrate without using GaN NWs as the template, by plasma-assisted molecular beam epitaxy. Our newly developed process elucidates that depending on the substrate temperature and V/III ratio an AlGaN network is formed on sapphire substrate prior to the NWs growth. We find that the ledges of this kinked shaped network act as nucleation sites for the NW growth.