title: Coherent phonon anisotropy in aligned single-walled carbon nanotubes.
abstract: By time-resolved reflectivity measurements with sub-10 fs laser pulses at 395 nm, the coherent phonons of aligned bundles of single-walled carbon nanotubes are observed for various polarization directions of the pump and probe pulses. In the isotropic reflectivity measurement, we observe the radial breathing modes, G, and even D modes, while in the anisotropic reflectivity mode, only the G mode appears. A complex polarization dependence of the G band phonon amplitude in the isotropic reflectivity is explained by the superposition of G band phonons with different symmetries.
authors.affiliation: Advanced Nano Characterization Center, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Kato
authors.forename: Kunie
authors.initials: K
authors.lastname: Ishioka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kitajima
authors.forename: Jie
authors.initials: J
authors.lastname: Tang
authors.forename: Riichiro
authors.initials: R
authors.lastname: Saito
authors.forename: Hrvoje
authors.initials: H
authors.lastname: Petek
mesh_terms: D016880:Anisotropy; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods; D013059:Spectrum Analysis, Raman / Q000379:methods; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: D037742:Nanotubes, Carbon