Optical Properties of Active Ions Around the Ferro-Paraelectric Phase Transition in SBN Crystals

New results on the evolution of the emission of Nd ³⁺ doped Sr _x Ba _{1− x} Nb ₂ O ₅ crystal during the ferroelectric phase transition are presented and compared to those previously obtained for Cr ³⁺ and Yb ³⁺ doped Sr _x Ba _{1− x} Nb ₂ O ₅ . We have observed that Nd ³⁺ emission is insensitive to the structural changes suffered by the crystal during the phase transition, contrary to the observations obtained for the cases of the Cr ³⁺ and Yb ³⁺ doped crystals. The results are interpreted in terms of the different lattice sites occupied by the optically active ions in the Sr _x Ba _{1− x} Nb ₂ O ₅ crystal.

Keywords:

• SHG
• phase transitions
• nonlinear properties

Acknowledgments

Paper originally presented at IMF-11, Iguassu Falls, Brazil, September 5–9, 2005; received for publication January 26, 2006.