Inductive type properties of FeCoZr–CaF2 and FeCoZr–PZT nanocomposites

Abstract

The paper presents investigations into frequency dependences of conductivity, capacitance and the phase angle θ for nanocomposites (FeCoZr)x(CaF2)(100−x) and (FeCoZr)x(PZT)(100−x). The nanocomposites have been produced with the application of ion-beam sputtering using pure argon ions (oxygen-free materials) and mixed ions of argon and oxygen (oxygen materials). The phase angle versus frequency characteristics for the oxygen nanocomposites show a transition from negative to positive phase angle values along with the frequency increase. The maximum observed phase angle θ values reach beyond the 90°. The phase angle transition through 0° is accompanied with the voltage resonance phenomenon that is represented by strong minima in the capacitance versus frequency curves. In the conductivity versus frequency characteristics, strong minima occur during the phase angle θ transition through 90°, which corresponds to the occurrence of current resonance. Occurrence of the coilless inductance features in nanocomposites (FeCoZr)x(PZT)(100−x) and (FeCoZr)x(CaF2)(100−x), produced with the ion-beam sputtering using argon and oxygen ions, is related to the formation of a subsurface layer of metal oxides on the metallic phase nanogranules.