It was observed experimentally by Rouviere et al. (1999) that GaN/AlN quantum dots nucleated at the edge of threading dislocations. The preferred nucleation of quantum dots in this way was generally assumed to be due to the influence of the stress/strain field around the dislocation core, which in turn, gives the chemical and geometric conditions for nucleation of the quantum dots. The finite element problem was solved for quantum dots situated at the edge of threading dislocations where various lattice parameters, piezoelectric and spontaneous polarization coefficients were assumed for the quantum dot and its matrix. By solving the elastic and electric equilibrium problems, both the residual stress and electric fields were obtained. The computational scheme used was obtained by linking 2 previous finite-element algorithms (Dłużewski et al., 2004) and (Jurczak et al., 2005; Lepkowski et al., 2005). This approach led to a deeper physical insight into the mechanics and electrical properties of quantum dots, and ultimately determine the efficiency of light emission.

Nonlinear Piezoelectric Properties of GaN Quantum Dots Nucleated at the Edge of Threading Dislocations. P.Dłużewski, T.D.Young, G.Jurczak, J.A.Majewski: Physica Status Solidi C, 2007, 4[7], 2399-402