Transport properties and magnetic ordering in iron-doped NbSe2

The resistivity $\ensuremath{\rho}$ and Hall coefficient ${R}_{H}$ are reported for ${\mathrm{Fe}}_{x}\mathrm{Nb}{\mathrm{Se}}_{2}$ for $0.005<~x<~0.33$ over the entire temperature range for 1.5 to 300 K. The magnetic state of the iron dramatically affects these transport properties. At low concentrations the transport properties appear to reflect a Kondo-like interaction between the iron moment and the charge carriers. In the intermediate concentration range anomalous behavior in both $\ensuremath{\rho}$ and ${R}_{H}$ is consistent with the iron forming a spin-glass or spin-density-wave state. At still higher concentrations an antiferromagnetic state is indicated. These states are in agreement with susceptibility measurements. Anisotropic behavior in ${R}_{H}$ and in the susceptibility and the unusual behavior of the transport properties lead to a model of an anisotropic spin-glass state in which only the spin component perpendicular to the layers is "locked."