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arXiv · 1406.0773

Unifying the low-temperature photoluminescence spectra of carbon nanotubes: the role of acoustic phonon confinement

Fabien Vialla·Yannick Chassagneux·Robson Ferreira·Cyrielle Roquelet·Carole Diederichs·Guillaume Cassabois·Philippe Roussignol·Jean-Sébastien Lauret·Christophe Voisin
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Abstract

At low temperature the photoluminescence of single-wall carbon nanotubes show a large variety of spectral profiles ranging from ultra narrow lines in suspended nanotubes to broad and asymmetrical line-shapes that puzzle the current interpretation in terms of exciton-phonon coupling. Here, we present a complete set of photoluminescence profiles in matrix embedded nanotubes including unprecedented narrow emission lines. We demonstrate that the diversity of the low-temperature luminescence profiles in nanotubes originates in tiny modifications of their low-energy acoustic phonon modes. When low energy modes are locally suppressed, a sharp photoluminescence line as narrow as 0.7 meV is restored. Furthermore, multi-peak luminescence profiles with specific temperature dependence show the presence of confined phonon modes.

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Fabien Vialla, Yannick Chassagneux, Robson Ferreira, Cyrielle Roquelet, Carole Diederichs, Guillaume Cassabois, Philippe Roussignol, Jean-Sébastien Lauret, Christophe Voisin. 2014-06-03. Unifying the low-temperature photoluminescence spectra of carbon nanotubes: the role of acoustic phonon confinement. https://doi.org/10.1103/physrevlett.113.057402

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