title: Higher-order nonlinear electromechanical effects in wurtzite GaN/AlN quantum dots.
abstract: As we demonstrated earlier, conventional mathematical models based on linear approximations may be inadequate in the analysis of properties of low-dimensional nanostructures and band structure calculations. In this work, a general three-dimensional axisymmetric coupled electromechanical model accounting for lattice mismatch, spontaneous polarization and higher-order nonlinear electrostriction effects has been applied to analyze properties of GaN/AlN quantum dots coupled with wetting layer. The generalized model that accounts for five independent electrostriction coefficients has been solved numerically via a finite-element implementation. The results, exemplified for truncated conical GaN/AlN quantum dots, demonstrate that the effect of nonlinear electrostriction in GaN/AlN nanoheterostructure quantum dots could be significant. In particular, the influence of nonlinear electromechanical effects on optoelectronic properties is highlighted by the results on band structure calculations based on a multiband effective mass theory.
authors.affiliation: M2NeT Laboratory, Wilfrid Laurier University, 75 University Avenue W, Waterloo, ON, N2L 3C5, Canada.
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Bahrami-Samani
authors.forename: Sunil R
authors.initials: SR
authors.lastname: Patil
authors.forename: Roderick
authors.initials: R
authors.lastname: Melnik