The interaction of a exciton confined in a semiconductor quantum dot (QD) with bulk phonons (acoustical and optical) responsible for the exciton dephasing is studied. The decoherence of the exciton due to the creation of a polaron with long-living or decaying phonons is described. Characteristic dephasing times for an InAs / GaAs QD are estimated using Green function methods in order to determine fundamental time limitations for use of the QD exciton in quantum information processing.
Quantum-information processing with ferroelectrically coupled quantum dots
