Optimization of the anharmonic strain model to capture realistic strain distributions in quantum dots

Self-assembled quantum dots are highly strained heterostructures, and a rigorous atomistic strain model is needed to predict the behavior of these devices. An anharmonic strain model reported by Lazarenkova, et al. [1] modifies the well-known harmonic Keating model [2] to include the effect of anharmonicity in the lattice potential. The Lazarenkova strain parameters were originally optimized to deliver correct Grüneisen parameters, however this optimization does not provide strain values that compare well to the values obtained in experiments on both quantum wells and dots. Our new approach in optimizing the model parameters to obtain correct biaxial strain ratio in quantum wells has resulted in a significant improvement in the quantum dot simulations in terms of reproducing experimental optical transitions.