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We revisit correlation effects in doped metallic zigzag carbon nanotubes by using both the one-loop renormalization group and non-perturbative bosonization techniques. Note that, if a nanotube is placed near a conducting plate, the long-range Coulomb interactions are screened and the resulting short-range interactions can be modelled by on-site and nearest-neighbor repulsive interactions $U$, $V$ and $V_{perp}$ respectively. Using both analytic and numeric means, we determine the phase diagram of the ground states. For $U/t<0.5$ ($t$ is the hopping strength), dynamical symmetry enlargement occurs and the low-energy excitations are described by the SO(6) Gross-Neveu model. However, for realistic material parameters $U/t sim mathcal{O}(1)$, the charge sector decouples but there remains an enlarged SO(4) symmetry in the spin sector.
We investigate a metallic zigzag carbon nanotube by means of a Hubbard model which includes both on-site and nearest neighbour interactions. Assuming weak interactions, a renormalization group analysis of the equivalent two-leg ladder followed by bos
We study spin-orbit coupling in metallic carbon nanotubes (CNTs) within the many-body Tomonaga-Luttinger liquid (TLL) framework. For a well defined sub-class of metallic CNTs, that contains both achiral zig-zag as well as a sub-set of chiral tubes, a
We report on the spin dynamics of 13C isotope enriched inner-walls in double-wall carbon nanotubes (DWCNT) using 13C nuclear magnetic resonance (NMR). Contrary to expectations, we find that our data set implies that the spin-lattice relaxation time (
We show that the photoluminescence intensity of single-walled carbon nanotubes is much stronger in tubes with large chiral angles - armchair tubes - because exciton resonances make the luminescence of zigzag tubes intrinsically weak. This exciton-exc
The dynamical conductance of electrically contacted single-walled carbon nanotubes is measured from dc to 10 GHz as a function of source-drain voltage in both the low-field and high-field limits. The ac conductance of the nanotube itself is found to