Growing self-assisted GaAs nanowires up to 80 μm long by molecular beam epitaxy

Ultralong GaAs nanowires were grown by molecular beam epitaxy using the vapor-liquid-solid method. In this ultralong regime we show the existence of two features concerning the growth kinetic and the structural properties. Firstly, we observed a non-classical growth mode, where the axial growth rate is attenuated. Secondly, we observed structural defects at the surface of Wurtzite segments located at the bottom part of the nanowires. We explain these two phenomena as arising from a particular pathway of the group V species, specific to ultralong nanowires. Finally, the optical properties of such ultralong nanowires are studied by photoluminescence experiments.

Automated summary

In this study, ultralong GaAs nanowires were successfully grown by vapor-liquid-solid method. The research revealed two features in terms of growth kinetic and structural properties. Firstly, a non-classical growth mode with attenuated axial growth rate was observed. Secondly, structural defects were found at the surface of Wurtzite segments located at the bottom of the nanowires. These phenomena were explained as a result of a specific pathway of the group V species in ultralong nanowires. In addition, the optical properties of the ultralong nanowires were studied using photoluminescence experiments.