Frequency dependence of the switching polarisation in PZT ceramics

Abstract

The performance of many ferroelectric-based devices depends fundamentally of the polarisation reversal characteristics. In this work, we report results on the frequency dependence of the hysteresis loops in Pb(Zr, Ti)O₃ ceramics modified with Nb₂O₅ or Fe₃O₅. The polarisation reversal properties were greatly modified by doping effect. The results revealed that for Pb(Zr, Ti)O₃ doped with Nb₂O₅ important ferroelectric features such as coercive field, polarisation and backswitching were strongly frequency dependent. Opposite behaviour was found for Pb(Zr, Ti)O₃ doped with Fe₃O₅. In addition, Fe₃O₅ also decreased the polarisation and increased considerably the backswitching effect. The results are discussed in terms of the 90° domain walls motion and their relationships with both the frequency of the electric field and the doping effect.

Key Words:

• Domain
• Frequency
• Reorientation
• polarisation.