Structural Properties, Impedance Spectroscopy and Dielectric Spin Relaxation of Ni-Zn Ferrite Synthesized by Double Sintering Technique

TL;DR

This study investigates how sintering temperature affects the structural, dielectric, and relaxation properties of Ni-Zn ferrite ceramics, revealing long dielectric relaxation times suitable for spintronic applications.

Contribution

It provides detailed analysis of impedance and dielectric behavior of Ni-Zn ferrite with varying sintering temperatures, explaining the phenomena with models like Rezlescu and electric modulus formalism.

Findings

Dielectric constants increase with sintering temperature.

Long dielectric relaxation times (nanoseconds) are observed.

Impedance spectra are explained by two parallel RC circuits.

Abstract

Structural properties, impedance, dielectric and electric modulus spectra have been used to investigate the sintering temperature (Ts) effect on the single phase cubic spinel Ni0.6Zn0.4Fe2O4 (NZFO) ceramics synthesized by standard ceramic technique. Enhancement of dielectric constants is observed with increasing Ts. The collective contribution of n-type and p-type carriers yields a clear peak in notable unusual dielectric behavior is successfully explained by the Rezlescu model. The non-Debye type long range dielectric relaxation phenomena is explained by electric modulus formalism. Fast response of the grain boundaries of the sample sintered at lower Ts sample leading to small dielectric spin relaxation time, t (several nanoseconds) have been determined using electric modulus spectra for the samples sintered at different Ts. Two clear semicircles in impedance Cole-Cole plot have also been successfully explained by employing two parallel RC equivalent circuits in series configuration taking into account no electrode contribution. Such a long relaxation time in NZFO ceramics could suitably be used in nanoscale spintronic devices.