Microstructure and negative magnetoresistance in pitch-derived carbon fibres
- Journal of Physics D: Applied Physics, 24(5), p.714-718, 1991 .
The transverse magnetoresistance of various pitch-derived carbon fibres has been measured at 4.2 and 77 K as a function of magnetic field up to 1.2 T. The magnetoresistance was found to be negative for all the fibres studied. The data have been interpreted using the two-dimensional (2D)weak localization theory and have been related to the structural parameters determined by X-ray diffraction. The results are also compared with those obtained on other pitch-based fibres and on pregraphitic carbons. They show that the negative magnetoresistance is related to the microstructure of the material and thus could be used as a tool to characterize the defect structure of carbon fibres.