We have investigated the carrier dynamics and activation energy of CdxZn(1-x)Te/ZnTe quantum dots (QDs) on GaAs and Si substrates. The carrier dynamics of QDs on GaAs and Si substrates is studied using time-resolved photoluminescence (PL) measurements, revealing shorter exciton lifetimes of QDs on Si substrate. In particular, the activation energy of electrons confined in QDs on the GaAs substrate, as obtained from temperature-dependent PL spectra, is higher than that of electrons confined in QDs on the Si substrate.
View Article and Find Full Text PDFTunable-white-light-emitting materials are developed by combining two single-crystal oxide nanowire materials-ZnO and SnO(2)-having different light emissions. The tuning of white-light emission from cool white to warm white is achieved for the first time by adjusting the growth sequence and growth time of the ZnO and SnO(2) nanowires. Combined ZnO:SnO(2) nanowire arrays yield a desired emission color from (0.
View Article and Find Full Text PDFTriggered single-photon emission from a single CdTe quantum dot (QD) grown on Si(001) substrate is demonstrated for the first time. The emission wavelength of QDs can be tuned in a wide spectral range (more than 8 meV) using a focused laser beam. A nearly perfect single-photon emission from the exciton lines is preserved even after energy tuning.
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