title: Excitonic optical properties of wurtzite ZnS quantum dots under pressure.
abstract: By means of atomistic empirical pseudopotentials combined with a configuration interaction approach, we have studied the optical properties of wurtzite ZnS quantum dots in the presence of strong quantum confinement effects as a function of pressure. We find the pressure coefficients of quantum dots to be highly size-dependent and reduced by as much as 23% in comparison to the bulk value of 63 meV/GPa obtained from density functional theory calculations. The many-body excitonic effects on the quantum dot pressure coefficients are found to be marginal. The absolute gap deformation potential of quantum dots originates mainly from the energy change of the lowest unoccupied molecular orbital state. Finally, we find that the exciton spin-splitting increases nearly linearly as a function of applied pressure.
authors: Materials Science Department, University of Patras, 26504 Patras, Greece.
authors: Zaiping
authors: Z
authors: Zeng
authors: Materials Science Department, University of Patras, 26504 Patras, Greece.
authors: Christos S
authors: CS
authors: Garoufalis
authors: Materials Science Department, University of Patras, 26504 Patras, Greece.
authors: Sotirios
authors: S
authors: Baskoutas
authors: Institut für Physikalische Chemie, Universität Hamburg, 20146 Hamburg, Germany.
authors: Gabriel
authors: G
authors: Bester