Ultrafast Dynamics of the First Excited-State of Quasi Monodispersed Single-Walled (9,7) Carbon Nanotubes

Time-resolved two color pump/probe spectroscopy was used to unravel the dynamics of ultrafast decay occurring upon population of the first optical bright excitonic level (E₁₁) in quasi-monodispersed, polymer-wrapped, single-walled (9,7)-carbon nanotubes (SWNTs) in toluene at room temperature. After resonant E₁₁ excitation, transfer of population to at least one optically dark level near E₁₁ was observed to take place within the first picosecond. In addition, phonon-assisted E₁₁-excitation led to transients similar to those observed upon resonant E₁₁-excitation indicating ultrafast vibrational relaxation convoluted with the temporal resolution of 60 fs