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Doping- and size-dependent suppression of tunneling in carbon nanotubes

S. Bellucci·J. Gonzalez·P. Onorato
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Abstract

We study the effect of doping in the suppression of tunneling observed in multi-walled nanotubes, incorporating as well the influence of the finite dimensions of the system. A scaling approach allows us to encompass the different values of the critical exponent $α$ measured for the tunneling density of states in carbon nanotubes. We predict that further reduction of $α$ should be observed in multi-walled nanotubes with a sizeable amount of doping. In the case of nanotubes with a very large radius, we find a pronounced crossover between a high-energy regime with persistent quasiparticles and a low-energy regime with the properties of a one-dimensional conductor.

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S. Bellucci, J. Gonzalez, P. Onorato. 2003-04-04. Doping- and size-dependent suppression of tunneling in carbon nanotubes. https://doi.org/10.1103/physrevb.69.085404

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