Quantum Dot To Quantum Wire Transition Of M-Plane Gan Islands

Structural studies of m-plane GaN quantum dots and quantum wires are presented. A shape transition responsible for the evolution of quantum dots into quantum wires is put in evidence and shown to depend on the amount of material deposited. In addition, it is established that vertical correlation of successive nanostructure planes may also induce the dot-wire shape transition. Consistent with theoretical predictions, it is proposed that the shape transition results from an elastic energy minimization process made possible by an easy adatom diffusion along [11-20] direction.