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Van Hove Singularities in disordered multichannel quantum wires and nanotubes

S. Huegle·R. Egger
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Abstract

We present a theory for the van Hove singularity (VHS) in the tunneling density of states (TDOS) of disordered multichannel quantum wires, in particular multi-wall carbon nanotubes. We assume close-by gates which screen off electron-electron interactions. Diagrammatic perturbation theory within a non-crossing approximation yields analytical expressions governing the disorder-induced broadening and shift of VHS's as new subbands are opened. This problem is nontrivial because the (lowest-order) Born approximation breaks down close to the VHS. Interestingly, compared to the bulk case, the boundary TDOS shows drastically altered VHS, even in the clean limit.

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BibTeXRIS

S. Huegle, R. Egger. 2002-10-17. Van Hove Singularities in disordered multichannel quantum wires and nanotubes. https://doi.org/10.1103/physrevb.66.193311

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