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arXiv · 0805.0246

Computational study of exciton generation in suspended carbon nanotube transistors

Siyuranga O. Koswatta·Vasili Perebeinos·Mark S. Lundstrom·Phaedon Avouris
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Abstract

Optical emission from carbon nanotube transistors (CNTFETs) has recently attracted significant attention due to its potential applications. In this paper, we use a self-consistent numerical solution of the Boltzmann transport equation in the presence of both phonon and exciton scattering to present a detailed study of the operation of a partially suspended CNTFET light emitter, which has been discussed in a recent experiment. We determine the energy distribution of hot carriers in the CNTFET, and, as reported in the experiment, observe localized generation of excitons near the trench-substrate junction and an exponential increase in emission intensity with a linear increase in current versus gate voltage. We further provide detailed insight into device operation, and propose optimization schemes for efficient exciton generation; a deeper trench increases the generation efficiency, and use of high-k substrate oxides could lead to even larger enhancements.

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Siyuranga O. Koswatta, Vasili Perebeinos, Mark S. Lundstrom, Phaedon Avouris. 2008-05-02. Computational study of exciton generation in suspended carbon nanotube transistors. https://doi.org/10.1021/nl0801226

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