Atomistic simulation of GaAs/AlGaAs quantum dot/ring nanostructures

We report on numerical simulations of GaAs/Al_0.3Ga_0.7As complex quantum dot/ring nanostructure. Both the empirical tight-binding (ETB) model with a sp3d5s*+spin-orbit parametrization and k.p model are used to study the electronic properties of the complex quantum system. Graphical processing units (GPUs) are employed to carry out the ETB calculation within a reasonable time frame for systems with varying quantum dot size. The goal of our investigation is to fine tune the electronic properties of the complex nanostructure via size tuning, in order to find lambda states (coupled states) that are localized in both the quantum dot and quantum ring.