Plasma-assisted molecular beam epitaxy growth of GaN nanowires using indium-enhanced diffusion

It is shown that catalyst-free growth of well-separated GaN nanowires by plasma-assisted molecular beam epitaxy can be achieved at moderate temperature using an additional indium flux. The results are consistently interpreted by considering that thermally assisted or indium-assisted in-plane Ga adatom diffusion play an equivalent role, i.e., prevent growth of a two-dimensional GaN layer between nanowires, a necessary condition to their growth.