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arXiv · 1106.4993

All-optical trion generation in single walled carbon nanotubes

Silvia Santos·Bertrand Yuma·Stéphane Berciaud·Jonah Shaver·Mathieu Gallart·Pierre Gilliot·Laurent Cognet·Brahim Lounis
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Abstract

We present evidence of all optical trion generation and emission in undoped single walled carbon nanotubes (SWCNTs). Luminescence spectra, recorded on individual SWCNTs over a large CW excitation intensity range, show trion emission peaks red-shifted with respect to the bright exciton peak. Clear chirality dependence is observed for 22 separate SWCNT species, allowing for determination of electron-hole exchange interaction and trion binding energy contributions. Luminescence data together with ultrafast pump probe experiments on chirality sorted bulk samples suggest that exciton-exciton annihilation processes generate dissociated carriers that allow for trion creation upon a subsequent photon absorption event.

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Silvia Santos, Bertrand Yuma, Stéphane Berciaud, Jonah Shaver, Mathieu Gallart, Pierre Gilliot, Laurent Cognet, Brahim Lounis. 2011-06-24. All-optical trion generation in single walled carbon nanotubes. https://doi.org/10.1103/physrevlett.107.187401

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