Inelastic light scattering and light emission from single and double wall carbon nanotubes
نویسندگان
چکیده
We use inelastic light scattering (Raman) to probe individual and isolated single wall carbon nanotubes, suspended in air over trenches to explore the influence of the environment on the electronic transition energies. We find narrow and predominantly symmetric resonance profiles which are significantly downshifted as compared to isolated tubes in aqueous surfactant suspensions. A lower limit of the exciton binding energy in SWNTs is deduced by using the observed optical transition energies of SWNTs in SDS solutions. Photoluminescence is observed from narrow diameter double wall carbon nanotubes in aqueous surfactant suspensions.
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