Low temperature photoluminescence imaging and time-resolved spectroscopy of single CdS nanowires

摘要

Time-resolved photoluminescence (PL) and micro-PL imaging were used to studysingle CdS nanowires at 10 K. The low-temperature PL of all CdS nanowiresexhibit spectral features near energies associated with free and bound excitontransitions, with the transition energies and emission intensities varyingalong the length of the nanowire. In addition, several nanowires show spatiallylocalized PL at lower energies which are associated with morphologicalirregularities in the nanowires. Time-resolved PL measurements indicate thatexciton recombination in all CdS nanowires is dominated by non-radiativerecombination at the surface of the nanowires.