A photoemission study of the metallic ground state of potassium‐doped C60 peapods

Abstract

AbstractWe report on the doping dependence of the electronic structure of the valence band of mats of C60‐filled single wall carbon nanotubes (C60 peapods) studied by high resolution photoemission spectroscopy. In the pristine state, the bundles consist of approximately one third metallic tubes which are Tomonaga–Luttinger liquids (TLL) and thus show a power law scaling of the density of states near the Fermi level. The power law scaling factor of the pristine peapods is hardly increased compared to that of single‐walled carbon nanotubes (SWCNT). Upon doping we find a complex doping behavior and charge distribution between the electronic states of the SWCNT and the encaged C60 chains. Close to the Fermi level this has consequences on the doping induced crossover from a TLL to a conventional Fermi liquid which is found at a higher charge transfer as compared to intercalated SWCNT bundles. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)