We present numerical investigations based on the Luttinger-Kohn four-band k⋅p theory and, accordingly, establish a quantitatively valid model of the excitonic fine structures of droplet epitaxial GaAs/AlGaAs quantum dots under uni-axial stress control. In the formalisms, stressing a photo-excited quantum dot is equivalent creating a pseudo-magnetic field that is directly coupled to the pseudo-spin of the exciton doublet and tunable to tailor the polarized fine structure of exciton. The latter feature is associated with the valence-band-mixing of exciton that is especially sensitive to external stress in inherently unstrained droplet epitaxial GaAs/AlGaAs quantum dots and allows us to mechanically design and prepare any desired exciton states of QD photon sources prior to the photon generation.
@article{arxiv.1401.6331,
title = {Mechanically induced pseudo-magnetic fields in the excitonic fine structures of droplet epitaxial quantum dots},
author = {Shun-Jen Cheng and Yu-Huai Liao and Pei-Yi Lin},
journal= {arXiv preprint arXiv:1401.6331},
year = {2015}
}