Effect of High Pressure on the Relaxor Ferroelectrics Na 1/2 Bi 1/2 TiO 3  (NBT) and PbMg 1/3 Nb 2/3 O 3  (PMN)

Kreisel, J; Bouvier, P; Dkhil, B; Chaabane, B; Glazer, A M; Thomas, P.R.; Welberry, Thomas

Effect of High Pressure on the Relaxor Ferroelectrics Na 1/2 Bi 1/2 TiO 3 (NBT) and PbMg 1/3 Nb 2/3 O 3 (PMN)

Date

2004

Authors

Kreisel, J

Bouvier, P

Dkhil, B

Chaabane, B

Glazer, A M

Thomas, P.R.

Welberry, Thomas

Publisher

Taylor & Francis Group

Abstract

The aim of the present paper is to review and briefly discuss recent experimental results on the effect of high pressure (p > 1.5 GPa) on relaxor ferroelectrics, exemplified by Na1/2Bi1/2TiO3 and PbMg1/3Nb2/3O3. The main result is that relaxor ferroelectrics present important polar and structural pressure-instabilities, which lead to both phase transitions of the average structure and considerable changes of the local structure. It is in particular the observation of a pressure-induced suppression of the relaxor-characteristic X-ray diffuse scattering that points to important changes in the local order. The complementary use of Raman spectroscopy, X-ray diffraction and X-ray diffuse scattering allows the proposition of a mechanism for the observed changes.