Relaxor properties of SBN:CE

Abstract
Relaxor properties of Sr0.61-xBa0.39Nb2O6:Cex 3+ (SBN61:Ce) are examined by dielectric spectroscopy, linear birefringence (LB) and optical second harmonic generation (SHG) as a function of frequency and temperature before and after poling. Relaxor behavior with large polydispersivity is observed above the ferroelectric phase transition temperature Tc . Below Tc a long-range ordered ferroelectric state with low polydispersivity prevails. An Ornstein-Zenike analysis of LB data suggests that pure SBN61 belongs to the 3D Ising universality class. Doping with Ce3+ ions, which seem to act as random fields, enhances the relaxor properties.