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Resonant Coherent Phonon Generation in Single-Walled Carbon Nanotubes through Near-Band-Edge Excitation

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 نشر من قبل Junichiro Kono
 تاريخ النشر 2009
  مجال البحث فيزياء
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We have observed large-amplitude coherent phonon oscillations of radial breathing modes (RBMs) in single-walled carbon nanotubes excited through the lowest-energy (E11) interband transitions. In contrast to the previously-studied coherent phonons excited through higher-energy (E22) transitions, these RBMs show comparable intensities between (n-m) mod 3 = 1 and -1 nanotubes. We also find novel non-resonantly excited RBMs over an excitation range of ~300 meV above the E11 transition, which we attribute to multi-phonon replicas arising from strong exciton-phonon coupling.



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