Abstract

The dielectric properties of the Haldane gap compound Y2BaNiO5 were studied in the frequency range from 20 Hz to 1 MHz between 20 K and room temperature. This compound exhibits a high dielectric permittivity (ɛ′ ∼ 104) at room temperature below 100 kHz. Both dielectric relaxation and dc resistivity ρ follow the thermally activated process with similar value of the activation energy. This indicates the close correlation between the electric conduction and the dielectric polarization. The modulus spectra reveal evidence for both grain and grain boundary relaxation times. The grain relaxation time follows thermally activated process, whereas the grain boundary relaxation time exhibits variable range hopping (VRH) behavior. The observed giant dielectric response were explained in terms of internal (grain boundary) barrier layer capacitance (IBLC) effects.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call