Femtosecond Transient Absorption Spectroscopy of Single-Walled Carbon Nanotubes and their Ultrafast Optical Switching Behavior
Two types of individualized single-walled nanotubes (SWNTs) in aqueous surfactant suspensions have been studied by femtosecond two-color absorption spectroscopy. A careful selection of pump and probe wavelengths allows for the determination of the “intrinsic” lifetimes of the lowest excited states which depend on the diameter of the SWNTs. Furthermore, a fast decay component in the ps to sub-ps regime was also observed and tentatively attributed to bundle relaxation. Likewise, this experimental approach can also assess spectral regions with decays faster than 1 ps, which is of great interest for all-optical switching devices near the optical telecommunication wavelength.
Chunli BAI, Sishen XIE, Xing ZHU
J.P. Yang et al., "Femtosecond Transient Absorption Spectroscopy of Single-Walled Carbon Nanotubes and their Ultrafast Optical Switching Behavior", Solid State Phenomena, Vols. 121-123, pp. 905-908, 2007