Magnetoresistance scaling in the layered cobaltate Ca3Co4O9

TL;DR

This study explores the magnetoresistance and magnetization in Ca3Co4O9, revealing a spin-dependent diffusion mechanism and metallic-like conduction, providing new insights into the elementary excitations influencing transport properties.

Contribution

It demonstrates a scaling behavior between magnetoresistance and magnetization, linking spin-dependent diffusion to transport in layered cobaltates.

Findings

Negative magnetoresistance scales with magnetization

Transport crossover explained by spin-dependent diffusion

Metallic-like conduction persists across the temperature range

Abstract

We investigate the low temperature magnetic field dependences of both the resistivity and the magnetization in the misfit cobaltate Ca3Co4O9 from 60 K down to 2 K. The measured negative magnetoresistance reveals a scaling behavior with the magnetization which demonstrates a spin dependent diffusion 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 shed a new light on the nature of the elementary excitations relevant to the transport.