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Abstract: A practical oxidizing technique with ozone has been developed for the passivation of porous silicon (PS) at room temperature. The fundamental role of ozonization may be attributed to the strong oxidizing process for the Si–Hx species and dangling bonds. The subsequent 158 days’ aging effect with the presence of absorbed ozone molecules is very effective for the oxidizing process. At last we achieve a complete replacing Si–Hx coverage with Si-Ox film and Si–alkyl film. The steady increase of photoluminescence (PL) intensity is assigned to the increase in the barrier’s height efficiency and the increase in quantum confinement effect for the silicon nanocrystallites. [Copyright &y& Elsevier]

Abstract: The energy relaxation of hot electrons in ZnO films was investigated by the electric-field-dependent photoluminescence. From the high-energy tail of photoluminescence, the electron temperature of the hot electrons in ZnO was determined. Longitudinal optical phonon emission alone cannot explain the relationship between the electron temperature and the electron energy loss rate. Instead, it can be explained by a model based on a combination of both the acoustic and longitudinal optical phonon emissions. [Copyright &y& Elsevier]

Abstract: Photoluminescence (PL), PL excitation (PLE), and time-resolved PL were used to study effects of InGaAs layers on the optical properties of InAs/GaAs quantum dots (QDs). A rich fine structure in the excited states of confined excitons (up to n =4 quantum states) was observed, providing useful information to study the quantum states in the InAs/GaAs QDs. A significant redshift of the PL peak energy for the QDs covered by InGaAs layers was observed, attributing to the decrease of the QD strain and the lowing of the quantum confinement. [Copyright &y& Elsevier]