Formation of noncoil-like inductance in nanocomposites (Fe0,45Co0,45Zr0,10)x(Al2O3)1-x manufactured by ion-beam sputtering of complex targets in Ar+O2 atmosphere

Abstract

This paper investigates the inductive contribution to AC conductance in the granular nanocomposites (Fe0:45Co0:45Zr0:10)x(Al2O3)1-x. The initial nanocomposites studied were manufactured in Ar+O2 atmosphere by ion-beam sputtering of the target containing Fe0:45Co0:45Zr0:10 and alumina stripes and then subjected to the annealing procedure in air over the temperature range 373 K < Ta < 873 K. These samples, before and after annealing, were studied using the temperature 77 K < Tp < 300 K and frequency 50 Hz < f < 1 MHz dependences of a real part of the admittance. Analysis of the observed dependences for x < 0:5 demonstrated that in the studied samples the equivalent circuits with the capacitive and noncoil-like inductive contributions can be accomplished. Just in this case, the capacitive properties of RLC circuit with the phase angle -90 - 0 are exhibited at low frequencies and the inductive properties with 0 - +90 become apparent at high frequencies. A value of the critical frequency fR, where phase angle changes sign, depends on the metallic phase concentration x, measuring temperature Tp, and annealing temperature Ta.