ABSTRACT
We present an atomistic simulation of an InxGa1-xAs/GaAs quantum dot with a non-uniform composition, embedded in a GaAs matrix. Optimised empirical potentials are employed to model the interatomic interactions of up to ∼400,000 atoms in order to obtain dynamic relaxation through energy minimisation. A simulation of a quantum dot cleaved in the (110) plane is implemented, and simulated Scanning Tunnelling Microscopy topographical maps are obtained and compared with experimental maps. Finally another simulation of a capped quantum dot is implemented and the strain tensor is obtained directly from the relaxed positions of the individual atoms, revealing the nature of the lattice distortion in both the island and the capping layer.
