Raman stress mapping of CdS nanosheets

Abstract

Spatially resolved Raman scattering is used to probe the strain distribution in CdS nanosheets. We observe both significant strains and a significant strain gradient across the nanosheets. The magnitude of the strain suggests that electronic properties of the CdS nanosheets will be influenced as well. Using spatially resolved photoluminescence spectroscopy, we show that the band gap of the nanosheet experiences changes in the energy gap of 20 meV across the width of the nanosheet, which are consistent with our observations of the strain.