ANOMALOUS NEGATIVE MAGNETORESISTANCE IN KAPPA-(BEDT-TTF)2CU(SCN)2

The organic superconductor kappa-(BEDT-TTF)2Cu(SCN)2 shows a region of negative magnetoresistance (NM) just above the upper critical field. In order to gain further information about this effect, we have studie d its dependence on a number of parameters. The magnetoresistance has been measured as a function of field direction, sample temperature and current configuration. The temperature dependence of the resistance h as also been studied as a function of field applied at different angle s and with different current configurations The NM is found to be much more pronounced when the measuring current is in the inter-layer dire ction (j parallel-to a) and almost absent when the current is in the plane of molecular layers (j perpendicular-to a). This suggests that the NM is associated with carrier localisation in the inter-layer dire ction. However, for the former current orientation, the strongest NM i s observed when the magnetic field is in the inter-layer direction (i. e. j parallel-to B).