Using pre-designed trains of femtosecond optical pulses, we have selectively excited coherent phonons of the radial breathing mode of specific-chirality single-walled carbon nanotubes within an ensemble sample. By analyzing the initial phase of the phonon oscillations, we prove that the tube diameter initially increases in response to ultrafast photoexcitation. Furthermore, from excitation profiles, we demonstrate that an excitonic absorption peak of carbon nanotubes periodically oscillates as a function of time when the tube diameter undergoes radial breathing mode oscillations.
@article{arxiv.0805.2206,
title = {Chirality-Selective Excitation of Coherent Phonons in Carbon Nanotubes},
author = {J. -H. Kim and K. -J. Han and N. -J. Kim and K. -J. Yee and Y. -S. Lim and G. D. Sanders and C. J. Stanton and L. G. Booshehri and E. H. Haroz and J. Kono},
journal= {arXiv preprint arXiv:0805.2206},
year = {2009}
}