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arXiv · 1203.3224

Fano Resonances in Mid-Infrared Spectra of Single-Walled Carbon Nanotubes

François Lapointe·Étienne Gaufrés·Isabelle Tremblay·Nathalie Y-Wa Tang·Patrick Desjardins·Richard Martel
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Abstract

This work revisits the physics giving rise to the carbon nanotubes phonon bands in the mid- infrared. Our measurements of doped and undoped samples of single-walled carbon nanotubes in Fourier transform infrared spectroscopy show that the phonon bands exhibit an asymmetric lineshape and that their effective cross-section is enhanced upon doping. We relate these observations to electron-phonon coupling or, more specifically, to a Fano resonance phenomenon. We note that only the dopant-induced intraband continuum couples to the phonon modes and that defects induced in the sidewall increase the resonance probabilities.

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François Lapointe, Étienne Gaufrés, Isabelle Tremblay, Nathalie Y-Wa Tang, Patrick Desjardins, Richard Martel. 2012-03-14. Fano Resonances in Mid-Infrared Spectra of Single-Walled Carbon Nanotubes. https://doi.org/10.1103/physrevlett.109.097402

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