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Photon-assisted transport in a carbon nanotube

P. A. Orellana·M. Pacheco
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Abstract

We investigate the quantum transport through a single-wall carbon nanotube connected to leads in the presence of an external radiation field. We analyze the conductance spectrum as a function of the frequency and strength of the field. We found that above a critical value of the field intensity, an enhancement of the conductance, or suppressed resistance, as a function of the field strength occurs. The conductance increases displaying oscillations which amplitude shows a strong dependence on the field frequency. For low radiation energies in comparison to the lead-CNT coupling energies, the oscillations evolve toward a structure of well defined steps in the conductance. We have shown that in this range of frequencies the field intensity dependence of the conductance can give direct information of single-walled carbon nanotubes energy spectra.

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P. A. Orellana, M. Pacheco. 2006-11-14. Photon-assisted transport in a carbon nanotube. https://doi.org/10.1103/physrevb.75.115427

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