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Ab initio simulations of excited carrier dynamics in carbon nanotubes

Yoshiyuki Miyamoto·Angel Rubio·David Tomanek
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Abstract

Combining time-dependent density functional calculations for electrons with molecular dynamics simulations for ions, we investigate the dynamics of excited carriers in a (3,3) carbon nanotube at different temperatures. Following an hv=6.8 eV photoexcitation, the carrier decay is initially dominated by efficient electron-electron scattering. At room temperature, the excitation gap is reduced to nearly half its initial value after ~230 fs, where coupling to phonons starts dominating the decay. We show that the onset point and damping rate in the phonon regime change with initial ion velocities, a manifestation of temperature dependent electron-phonon coupling.

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Yoshiyuki Miyamoto, Angel Rubio, David Tomanek. 2006-08-26. Ab initio simulations of excited carrier dynamics in carbon nanotubes. https://doi.org/10.1103/physrevlett.97.126104

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