Dielectric behaviour in Cu-Zn ferrites

Room temperature dielectric constant ε' and loss tangent tanδ of the spinel copper-zinc ferrite system have been studied as a function of composition in the frequency range 60Hz to 10MHz. High values of the order of 102 -104 of ε'and its high frequency dispersion in the low frequency range is explained in terms of Koops theory. All samples exhibit normal behaviour of ε' and tanδ with frequency. Their values decrease with increase in zinc content up to x = 0.6 followed by an increase with further increase in x value. This could be attributed to the existence of two types of charge carriers created during the sintering process. (author)