Ferroelectric Phase Transition in Cu-doped BaTiO3 Crystals

Authors

  • A. Ouedraogo University of Ouagadougou
  • K. Palm
  • G. Chanussot

DOI:

https://doi.org/10.3329/jsr.v1i2.1876

Keywords:

Ferroelectric transition, BaTiO3 single crystals, Thermo-currents, Dielectric constant.

Abstract

The paper examines the ferroelectric-paraelectric phase transition in Cu:BaTiO3 single crystals. Using thermo-currents and dielectric measurements, we found for pure samples the phase transition temperature to be close to Curie temperature (Tc=120°C) with an anisotropy of the dielectric constantε.The lowering of temperature Tm, corresponding to the maximum of pyroelectric signal, with the increase of concentration of impurities is confirmed by measurements of ε. Moreover, the e(T) curves show progressive broadening as well as higher peak with the increase of  impurity concentration, and the transition becomes more and more diffuse. The same effect occurs when the samples are subjected to a laser irradiation (λ=5145Ǻ). During annealing, crystals lose copper and Tm is thereafter observed to increase again. BaTiO3 is a displacive ferroelectric (having high permittivity k-values) which undergoes a first order phase transition. Ions substitutions have an effect on the lattice dynamics attributed to charge transfer to Ti and a lowering of elastic forces in BaTiO3.

 

Kewwords: Ferroelectric transition; BaTiO3 single crystals; Thermo-currents; Dielectric constant.

 

© 2009 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.

 

DOI: 10.3329/jsr.v1i2.1876

 

 

Downloads

Download data is not yet available.
Abstract
752
PDF
1051

Author Biographies

A. Ouedraogo, University of Ouagadougou

Assistant Professor Laboratory of Applied Organic Chemistry and Physics

K. Palm

Ph. D. in Physics, Research Assistant, Laboratory of Applied Organic Chemistry and Physics, UFR/SEA University of Ouagadougou BP 7021 Ouagadougou 03 Burkina Faso.

G. Chanussot

 CHANUSSOT Guy 2� (deceased) 

Ph.D. in Physics, Professor, Laboratory of Dielectrics University of Dijon 21000 Dijon France.

Downloads

Published

2009-04-21

How to Cite

Ouedraogo, A., Palm, K., & Chanussot, G. (2009). Ferroelectric Phase Transition in Cu-doped BaTiO3 Crystals. Journal of Scientific Research, 1(2), 192–199. https://doi.org/10.3329/jsr.v1i2.1876

Issue

Section

Section A: Physical and Mathematical Sciences