Photoluminescence of tetrahedral quantum-dot quantum wells.
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 nonadiabatic 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.
Fonoberov
Vladimir A
VA
Laboratory of Physics of Multilayer Structures, Department of Theoretical Physics, State University of Moldova, A. Mateevici 60, MD-2009 Chişinău, Moldova.
Pokatilov
Evghenii P
EP
Fomin
Vladimir M
VM
Devreese
Jozef T
JT