Magnetoresistance scaling in the layered cobaltate Ca 3 Co 4 O 9

International audienceWe investigate the low-temperature magnetic-field dependences of both the resistivity and the magnetization in the misfit cobaltate Ca 3 Co 4 O 9 from 60 K down to 2 K. The measured negative magnetoresistance reveals a scaling behavior with the magnetization which demonstrates a spin dependent scattering mechanism. This scaling is also found to be consistent with a shadowed metalliclike conduction over the whole temperature range. By explaining the observed transport crossover, this result sheds a new light on the nature of the elementary excitations relevant to the transport