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Radiative Lifetime of Excitons in Carbon Nanotubes

Vasili Perebeinos·J. Tersoff·Phaedon Avouris
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Abstract

We calculate the radiative lifetime and energy bandstructure of excitons in semiconducting carbon nanotubes, within a tight-binding approach. In the limit of rapid interband thermalization, the radiative decay rate is maximized at intermediate temperatures, decreasing at low temperature because the lowest-energy excitons are optically forbidden. The intrinsic phonons cannot scatter excitons between optically active and forbidden bands, so sample-dependent extrinsic effects that break the symmetries can play a central role. We calculate the diameter-dependent energy splittings between singlet and triplet excitons of different symmetries, and the resulting dependence of radiative lifetime on temperature and tube diameter.

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Vasili Perebeinos, J. Tersoff, Phaedon Avouris. 2005-06-29. Radiative Lifetime of Excitons in Carbon Nanotubes. https://doi.org/10.1021/nl051828s

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