Anisotropic polar state of Sr0.75Ba0.25Nb2O6 single crystal

Abstract

Relaxor and ferroelectric properties have been reported in a lot of compounds and solid solutions. There are usually several ways to tune the behaviour from relaxor to ferroelectric and vice versa: the chemical composition, the temperature and an applied electric field. We show here that the crystalline orientation is an additional tuning parameter. In the tetragonal tungsten bronze crystal Sr0.75Ba0.25Nb2O6, we have evidenced a ferroeletrictransition in the [100] direction while a relaxor state is found along the [001] direction. Moreover, these two different behaviours occur in the same temperature range. (c) 2006 Elsevier Masson SAS. All rights reserved.