Role of Zinc and Niobium in the Giant Piezoelectric Response of PbZn1/3Nb2/3O3 Auteur(s): Al-Zein A., Dammak Hichem, Papet Philippe, Mathon Olivier, Hehlen B., Levelut C., Haines Julien, Rouquette Jerome (Article) Publié: Inorganic Chemistry, vol. 53 p.3985 (2014) Texte intégral en Openaccess : Ref HAL: hal-01084087_v1 Ref Arxiv: 1412.3536 DOI: 10.1021/ic402409f WoS: 000334902400008 Ref. & Cit.: NASA ADS Exporter : BibTex | endNote 2 Citations Résumé: Relaxor ferroelectric perovskites are highly polarizable and can exhibit giant coupling between elastic strain and an applied electric field. Here, we report an in situ extended X-ray absorption fine structure (EXAFS) study of a PbZn1/3Nb2/3O3 (PZN) single crystal as a function of the electric field. We show that the strong dipoles in the NbO6 octahedra bonds are aligned along the four < 011 > directions close to the orientation of the electric field, while a small reversible polar shift occurs for Zn in the direction of the electric field, i.e., positive or negative. This reversible Zn-O polar shift is proposed to play an important role in both the "easy" switching of the ferroelectric polarization and the giant piezoelectric effect in PZN. |