Scientists have succeeded in the fabrication of axial heterostructures on catalyst free III-V nanowires. The growth of the wires is achieved from gallium/indium alloy droplets that are nucleated in situ. By variation of the In/Ga beam flux during the growth it was possible to vary the effective indium content up to x = 5%, as deduced from photoluminescence measurements. The heterostructures grown with the method presented were spatially mapped along the wires with confocal microphotoluminescence and cathodoluminescence. It was found as expected that the emission of GaAs/InxGa1−xAs/GaAs heterostructures is localized.

This work was the result of a collaboration between Ecole Polytechnique Federale de Lausanne (EPFL), the University of Lund, University of Barcelona and the Technical University of Munich.

The researchers presented their work in Nanotechnology.