Temperature dependent raman and photoluminescence of an individual Sn-doped CdS branched nanostructure

Abstract

Temperature dependent Raman spectra and photoluminescence, as well the Raman mapping of different parts in an individual Sn-doped CdS comb-like nanostructure reveal that the stronger electron–phonon coupling exist at the trunk-branch junctions than other parts. The Huang–Rhys factor was calculated and further confirms that the strong electron–phonon correlation at the junction. The localized deformation from the Sn dopant in the lattice leads to strong electron–phonon coupling at the local junction, which is proved by the scanning transmission electron microscope and energy dispersion spectrum. Moreover, the lifetime of near-band-edge emission and deep-level emission drastically increase with decreasing temperature, which both relate to the localized electron–phonon coupling and relaxation process. This work provides a clear description of the localized carrier correlation in the cross junction part of these branched nanostructures, which can be used to modulate the optoelectronic performance of micro/nanodevices.

Keywords

• CdS branched nanostructure
• temperature-dependent Raman
• photoluminescence
• electron-phonon coupling