Directly measured optical absorption cross sections for structure-selected single-walled carbon nanotubes.

Streit, Jason K; Bachilo, Sergei M; Ghosh, Saunab; Lin, Ching-Wei; Weisman, R Bruce · Nano Lett · 2014

basic_science · Level V

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Abstract

We have measured peak and spectrally integrated absolute absorption cross sections for the first (E11) and second (E22) optical transitions of seven semiconducting single-walled carbon nanotube (SWCNT) species in bulk suspensions. Species-specific concentrations were determined using short-wave IR fluorescence microscopy to directly count SWCNTs in a known sample volume. Measured cross sections per atom are inversely related to nanotube diameter. E11 cross sections are larger for mod 1 species than for mod 2; the opposite is found for E22.