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arXiv · 1608.04938

Doped carbon nanotubes as a model system of biased graphene

P. Szirmai·B. G. Márkus·B. Dóra·G. Fábián·J. Koltai·V. Zólyomi·J. Kürti·B. Náfrádi·L. Forró·T. Pichler·F. Simon
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Abstract

Albeit difficult to access experimentally, the density of states (DOS) is a key parameter in solid state systems which governs several important phenomena including transport, magnetism, thermal, and thermoelectric properties. We study DOS in an ensemble of potassium intercalated single-wall carbon nanotubes (SWCNT) and show using electron spin resonance spectroscopy that a sizeable number of electron states are present, which gives rise to a Fermi-liquid behavior in this material. A comparison between theoretical and the experimental DOS indicates that it does not display significant correlation effects, even though the pristine nanotube material shows a Luttinger-liquid behavior. We argue that the carbon nanotube ensemble essentially maps out the whole Brillouin zone of graphene thus it acts as a model system of biased graphene.

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P. Szirmai, B. G. Márkus, B. Dóra, G. Fábián, J. Koltai, V. Zólyomi, J. Kürti, B. Náfrádi, L. Forró, T. Pichler, F. Simon. 2016-08-17. Doped carbon nanotubes as a model system of biased graphene. https://doi.org/10.1103/physrevb.96.075133

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