nan Dresselhaus

'Buckypaper' from coaxial nanotubes

Double-walled carbon nanotubes are needed in a pure, highly crystalline form before features such as their electronic properties, thermal transport and mechanical behaviour can be investigated. Here we fabricate a paper-like material that consists of hexagonally packed bundles of clean, coaxial carbon nanotubes whose double walls vary little in diameter; it is prepared in high yields using chemical-vapour deposition with a conditioning catalyst and two-step purification. Our results will enable investigation of the physical properties of double-walled carbon nanotubes, which are predicted to be superior to those of both their single- and multiwalled relatives.

Temperature dependence of c-axis electrical resistivity and thermopower of graphite intercalation compounds

Results on the temperature variation from 2 lsim T lsim 300K of the c-axis electrical resistivity and thermopower of a donor stage-5 potassium and an acceptor stage-2 FeCl/sub 3/-graphite intercalation compounds are reported. Comparing the data with those of the literature reveals for both compounds a different qualitative behavior for low and high stages.

The Transport-properties of Activated Carbon-fibers

The transport properties of isotropic pitch-based carbon fibers with surface area 1000 m2/g have been investigated. We report preliminary results on the electrical conductivity, the magnetoresistance, the thermal conductivity, and the thermopower of these fibers as a function of temperature. Comparisons are made to transport properties of other disordered carbons.

Thermoelectric Properties of a Dilute Graphite Donor Intercalation Compound

Data on the in-plane thermal conductivity and thermoelectric power of a stage-5 potassium donor graphite intercalation compound are reported in the temperature range 3 < T < 300 K. In the lowest temperature range the electronic contribution dominates the thermal conductivity, while at higher temperature there is a dominant lattice contribution, which is much smaller than pristine graphite. The thermopower is negative in the whole temperature range.

The Ideal Resistivity of An Acceptor Graphite-intercalation Compound

Abstract Using a high-resolution system, the ideal electrical resistivity of a stage two CuCl2 benzene-derived graphite fiber intercalation compound is separated from the residual contribution from 4 K to 300 K. Contrary to what is observed in three-dimensional metals, the rate of increase of the ideal resistivity with temperature at high temperature is higher than that at lower temperature.

Comparison of transport properties in various semimetals systems

The common features in the electronic structure and transport properties of pure group V semimetals and of pristine graphite are discussed. Comparison is also made between the effect of doping the group V semimetals or intercalating pristine graphite on the band structure, the electrical and thermal conductivities, and the thermopower.