Presence of Inductivity in $(CoFeZr)_x(PZT)_{1-x}$ Nanocomposite Produced by Ion Beam Sputtering

This paper presents the investigations of the electrical properties of the $(CoFeZr)_{x}(PZT)_{1-x}$ nanocomposite with the metallic phase content x=43.8 at.%, which was produced by ion beam sputtering. Such preparation took place under an argon atmosphere with low oxygen content with its partial pressure $P_{O_2} = 2 \times 10^{-3} Pa$. The measurements were performed using alternating current within the frequency range of 50 Hz-10⁵ Hz for measuring temperatures ranging from 238 K to 328 K. The $(CoFeZr)_{43.8}(PZT)_{56.2}$ nanocomposite sample subjected to a 15 min annealing process in air at the temperature Tₐ=423 K demonstrates a phase angle of -90° ≤ θ ≤ 0° in the frequency range 50 Hz-10⁵ Hz. It corresponds to the capacitive type of conduction. In the frequency range 10⁴-10⁵ Hz sharp minima in selected conductivity vs. frequency characteristics occur, which corresponds to a current resonance phenomenon in RLC circuits. In case of a sample annealed at Tₐ=498 K the inductive type of conduction with 0° ≤ θ ≤ +90° occurs in a high frequency area. At the frequency $f_{r}$ characterized by the phase angle θ = 0°, the capacity value reaches its local minimum. It indicates a voltage resonance phenomenon in conventional RLC circuits. The θ = +90° crossing in the frequency dependence of phase angle corresponds to the current resonance phenomenon, which is represented by a strong local minimum in the conductivity vs. frequency characteristics.