Evolución con la presión de la constante dieléctrica en KNbO3 hasta 30 kbar
- E. Moya
- D. Errandonea
ISSN: 0366-3175
Year of publication: 1998
Volume: 37
Issue: 3
Pages: 227-229
Type: Article
More publications in: Boletín de la Sociedad Española de Cerámica y Vidrio
Abstract
The effect of pressure on the static dielectric constant (K) of single crystals of KNbOg is investigated by means of capacitance mea-surements. The dielectric constant increases with pressure up to 22.5 kbar, where it exhibits a large value (K= 5000), and then decre-ases. This change in its behavior is related to a phase transition induced by pressure. It is suggested that below 22.5 kbar, the pres-sure dependence of K obeys a Curie-Weiss-type law. As the large value of K is connected to a transverse optic soft mode, we have associated a displacive character to the induced phase transition. On decompression, the samples do not revert back to the ambient pressure phase.