Ab initio study on the electronic transport properties of carbon nanotube intramolecular junctions

Authors

  • R. N. Wang,

    1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, P.R. China
    2. Graduate School of the Chinese Academy of Sciences, 19A Yu Quan Rd, Beijing 100049, P.R. China
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  • X. H. Zheng,

    1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, P.R. China
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  • L. L. Song,

    1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, P.R. China
    2. Graduate School of the Chinese Academy of Sciences, 19A Yu Quan Rd, Beijing 100049, P.R. China
    3. School of Electronic Science and Applied Physics, Hefei University of Technology, Hefei 230009, P.R. China
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  • Z. Zeng

    Corresponding author
    1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, P.R. China
    • Phone: +86-551-5591407, Fax: +86-551-5591434
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Abstract

The effects of electron doping and molecule adsorption on the electronic transport properties of carbon nanotube (CNT) junctions CNT(3,3)/n-CNT(6,0)/CNT(3,3) (n = 1–5) are simulated by first-principles calculations combined with a non-equilibrium Green's function technique. The doping effects are investigated by N substitution for the carbon atom while the molecule adsorption effects are studied by adsorbing a H2O molecule or an OH group on the top of one carbon atom, respectively. The transmission function around the Fermi level is highly dependent on the doping or adsorption site. The effects are negligible when the site is at the interface, while it always forms a scattering barrier which causes a valley of the transmission spectra around the Fermi level when the doping/adsorption site is inside the sandwiched CNT(6,0). The conductance of CNT intramolecular junctions is very sensitive to the environment, which may provide potential of application in future nanoelectronic devices and gas sensors.

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