Mechanism of electrical conductivity in Nickel-Iron Ferrite

Measurements of the frequency dependence of the dielectric conductivity, Hall mobility, and thermal EMF as a function of temperature on polycrystalline Ni0.6Fe0.4Fe2O4indicate that these data can be interpreted in terms of the band model. Previous analyses of the semiconductor properties of ferrites according to the hopping model assume that the number of carriersnis identical with the concentration of divalent iron ions. Hall measurements indicate that this is not the case here, and thatnis best described by the equationn² = (ND-n)N₀[m*/m]3/2 g⁻¹ exp ({-ED}{kT}). Assigning a value of 2 tog , m*/mis 9.3, and EDis 0.034 eV.