Ultrafast relaxation dynamics of photoexcited states in semiconducting single-walled carbon nanotubes

We have experimentally investigated the relaxation dynamics of photoexcited states in semiconducting single-walled carbon nanotubes by means of femtosecond spectroscopy. The photoexcited electrons and holes are nonradiatively recombined via multi-phonon emission process within B1 ps: The tube diameter dependence of decay time suggests that the electron–phonon interaction is enhanced by decreasing the tube diameter. r 2002 Elsevier Science B.V. All rights reserved. PACS: 71.38; 78.47; 78.67.Ch