Taking into account the tetrahedral shape of a quantum dot quantum well (QDQW) when describing excitonic states, phonon modes and the exciton-phonon interaction in the structure, we obtain within a non-adiabatic approach a quantitative interpretation of the photoluminescence spectrum of a single CdS/HgS/CdS QDQW. We find that the exciton ground state in a tetrahedral QDQW is bright, in contrast to the dark ground state for a spherical QDQW. The position of the phonon peaks in the photoluminescence spectrum is attributed to interface optical phonons. We also show that the experimental value of the Huang-Rhys parameter can be obtained only within the nonadiabatic theory of phonon-assisted transitions.
@article{arxiv.cond-mat/0401651,
title = {Photoluminescence of tetrahedral quantum-dot quantum wells},
author = {V. A. Fonoberov and E. P. Pokatilov and V. M. Fomin and J. T. Devreese},
journal= {arXiv preprint arXiv:cond-mat/0401651},
year = {2009}
}