A vertical and lateral GaN/InGaN heterostructure within a nanowire has been grown by plasma assisted molecular beam epitaxy. The resulting wires have a complex morphology which results from a combination of vertical and lateral heterostructure interfaces. Photoluminescence indicates Indium content in the InGaN alloy of approximately 30 % and evidences in addition a high quality of the GaN nanowire. Raman investigation based on the analysis of the LO peak position and its shape reveal a composition variation between 20 % and 30 %. XRD measurements show a peak with an onset at 17.26 that extends to 16.6 also suggesting a spread in compositions. Transmission electron microscopy analysis indicates composition variations along the wire growth direction. In addition insight is gained about the position of the heterointerfaces. This allows an understanding of the complex shape of the nanowire.
Limbach, Friederich; Gotschke, Tobias; Stoica, Toma; Calarco, Raffaella;  JARA-Fundamentals of Future Information Technology (Germany)]; Sutter, E;  Cusco, Ramon; Artus, Luis 
- Institute of Bio- and Nanosystems (IBN-1), Research Center Juelich GmbH (Germany)
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York (United States)
- Institut Jaume Almera, Consell Superior d'Investigacions Cientifiques (CSIC), Barcelona, Catalonia (Spain)