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Anisotropic Decay Dynamics of Photoexcited Aligned Carbon Nanotube Bundles

Y. Hashimoto·Y. Murakami·S. Maruyama·J. Kono
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Abstract

We have performed polarization-dependent ultrafast pump-probe spectroscopy of a film of aligned single-walled carbon nanotube bundles. By taking into account imperfect nanotube alignment as well as anisotropic absorption cross sections, we quantitatively determined distinctly different photo-bleaching dynamics for polarizations parallel and perpendicular to the tube axis. For perpendicular polarization, we observe a slow (1.0-1.5 ps) relaxation process, previously unobserved in randomly-oriented nanotube bundles. We attribute this slower dynamics to the excitation and relaxation of surface plasmons in the radial direction of the nanotube bundles.

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Y. Hashimoto, Y. Murakami, S. Maruyama, J. Kono. 2006-12-31. Anisotropic Decay Dynamics of Photoexcited Aligned Carbon Nanotube Bundles. https://doi.org/10.1103/physrevb.75.245408

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