GIANT MAGNETORESISTANCE IN ACTINIDE SYSTEMS

In contrast to ferromagnetic uranium intermetallics, which exhibit lar ge drop below the ordering temperature, the resistivities of uranium a ntiferromagnets stay at much larger values below T(N). In this contrib ution, we demonstrate that a large portion of the residual resistance of uranium antiferromagnets can be removed by driving the compounds th rough metamagnetic transition to a field-aligned state. The consequenc e is the field-induced drop of resistance, which can exceed DELTArho/r ho(OT) = 90 %.