Search

The paper presents time-resolved incoherent anti-Stokes Raman spectroscopy (TRIARS) measurements of the population dynamics of G-mode phonons in semiconducting single-walled carbon nanotubes (SWCNTs), in which the G+ and G- dynamics are separated. The measurements were performed as a function of temperature over the full range 4-600 K, and at two laser excitation energies, 1.51 and 1.63 eV, which give TRIARS signals from SWCNTs in two different diameter distributions, 0.99 < d < 1.05 nm and 0.88 < d < 0.97 nm, respectively. The population lifetimes determined from the experiments were, to within experimental error, independent of mode type and diameter. In all cases the temperature dependence of the population lifetimes was well fitted by a model that assumes that two-phonon anharmonic decay is the dominant process and that the lower-energy daughter phonon has an energy of approximately 400 ± 100 cm-1. [ABSTRACT FROM AUTHOR]

We report time-resolved incoherent anti-Stokes Ramanscatteringmeasurements of the dynamics of the D and G′ bands in single-walledcarbon nanotubes at excitation energies of 1.51 and 1.63 eV over thetemperature range 4–330 K. The measurements indicate that thepopulation lifetimes (∼1 ps) of the phonons responsible forthe D band are dependent on nanotube type. The temperature dependenciesare consistent with anharmonic decay of the phonons into one low (<190cm–1) and one high energy phonon. [ABSTRACT FROM AUTHOR]