Electrical Transport Properties and Hopping Mechanism of ZrCuSiAs Type Compound GdFeAsO

Abstract

Iron-based ceramic GdFeAsO has been prepared using the solid-state reaction method. This material exhibits unique properties, showing superconductivity at extremely low temperatures and behaving as a semiconductor at high temperatures. Raman spectroscopy revealed various Raman active modes in the sample. UV-visible spectroscopy was employed to study the optical properties of the material in the wavelength range of 200-800 nm. Using Tauc's plot, the optical band energy values of the sample were estimated to be approximately 2.78 eV. The electrical characterizations have been performed through an impedance analyzer. Additionally, the sample displayed negative temperature coefficient of resistance behavior and positive temperature coefficient resistance. The thermistor parameters are evaluated using the bulk resistance at various temperatures. This opens up potential uses for thermistors in devices like fuses and temperature sensors. The ac conductivity spectrum of the sample followed both Jonscher's universal power law and the Arrhenius equation. The activation energy was calculated for different temperature regions. The correlated barrier hopping model is used to analyze the electrical conduction mechanism in the sample. This study provides insights into the unique electrical and optical properties of the GdFeAsO ceramic and sheds light on its potential applications in various fields.