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

TL;DR

This study uses low-temperature photoluminescence imaging and time-resolved spectroscopy to analyze exciton behavior and surface recombination in individual CdS nanowires, revealing spatial and spectral variations.

Contribution

It provides detailed spatial and spectral characterization of single CdS nanowires at low temperature using advanced PL techniques, highlighting surface effects and localized states.

Findings

Spectral features near exciton energies vary along nanowires.

Localized PL at lower energies linked to morphological irregularities.

Exciton recombination is dominated by surface non-radiative processes.

Abstract

Time-resolved photoluminescence (PL) and micro-PL imaging were used to study single CdS nanowires at 10 K. The low-temperature PL of all CdS nanowires exhibit spectral features near energies associated with free and bound exciton transitions, with the transition energies and emission intensities varying along the length of the nanowire. In addition, several nanowires show spatially localized PL at lower energies which are associated with morphological irregularities in the nanowires. Time-resolved PL measurements indicate that exciton recombination in all CdS nanowires is dominated by non-radiative recombination at the surface of the nanowires.