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arXiv · 1511.04918

Quantum Monte Carlo Calculations for Carbon Nanotubes

Thomas Luu·Timo A. Lähde
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Abstract

We show how lattice Quantum Monte Carlo can be applied to the electronic properties of carbon nanotubes in the presence of strong electron-electron correlations. We employ the path-integral formalism and use methods developed within the lattice QCD community for our numerical work. Our lattice Hamiltonian is closely related to the hexagonal Hubbard model augmented by a long-range electron-electron interaction. We apply our method to the single-quasiparticle spectrum of the (3,3) armchair nanotube configuration, and consider the effects of strong electron-electron correlations. Our approach is equally applicable to other nanotubes, as well as to other carbon nanostructures. We benchmark our Monte Carlo calculations against the two- and four-site Hubbard models, where a direct numerical solution is feasible.

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Thomas Luu, Timo A. Lähde. 2016-06-09. Quantum Monte Carlo Calculations for Carbon Nanotubes. https://doi.org/10.1103/physrevb.93.155106

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