Electronic Properties Of Single-walled Nanotubes Research Articles

Electronic and geometric structures of metallofullerene peapods

The electronic and geometric structures of the Sm-metallofullerene peapods (Sm@C 82) n @SWNTs, are investigated by in situ high-resolution transmission electron microscopy (HRTEM) and electron energy-loss spectroscopy (EELS). The obtained EELS spectra reveal that the encapsulated Sm ion takes +2 state in (Sm@C 82) n @SWNTs irrespective of the physical and the electronic properties of single-wall nanotubes.

Atomic structure and electronic properties of single-walled carbon nanotubes

Carbon nanotubes1 are predicted to be metallic or semiconducting depending on their diameter and the helicity of the arrangement of graphitic rings in their walls2,3,4,5. Scanning tunnelling microscopy (STM) offers the potential to probe this prediction, as it can resolve simultaneously both atomic structure and the electronic density of states. Previous STM studies of multi-walled nanotubes6,7,8,9 and single-walled nanotubes (SWNTs)10 have provided indications of differing structures and diameter-dependent electronic properties, but have not revealed any explicit relationship between structure and electronic properties. Here we report STM measurements of the atomic structure and electronic properties of SWNTs. We are able to resolve the hexagonal-ring structure of the walls, and show that the electronic properties do indeed depend on diameter and helicity. We find that the SWNT samples exhibit many different structures, with no one species dominating.