Spectral measurements in production of single-wall carbon nanotubes by laser ablation

Measurements are made of optical radiation from the luminous plume in a flow tube used to produce single-wall carbon nanotubes by laser ablation of graphite. Measurements include 10 μs exposures for a spectral region of 310–630 nm taken at several times after single and two-laser pulses and time-dependent measurements at a number of wavelengths. Strong emission from the C2 Swan bands and possibly from C3 are seen superimposed on a significant continuum the origin of which is uncertain. Temperatures estimated from ratios of intensities of Swan band features are in the range of 2500–4000 K.