InN/InGaN dot-in-a-wire nanostructures emitting at 1.55 µm

The room temperature photoluminescence emission at 1.55 µm from InN/In0.7Ga0.3N dot-in-nanowire heterostructures, which was grown on self-assembled GaN nanowires on Si (1 1 1) under N-rich condition by plasma assisted molecular beam epitaxy, has been clarified in this paper. The morphology of the nanowires was uniform along the c-axis as proved by scanning electron microscope, each of the nanowires was grown individually and homogeneously without any coalescence phenomenon respectively. The nanowires dispersed on a silicon substrate showed very clear InN dot-in-nanowire structure by high resolution transmission electron microscopy. The structural properties of the individual InGaN nanocolumn were further investigated by high-angle annular dark field image analysis and energy dispersive x-ray spectrum, which confirmed the successful growth of InN quantum dot embedded in InGaN nanowire.