LOW TEMPERATURE PROPERTIES OF Tb-DOPED Sr_1-xBa_xNb₂O₆ (SBN) CRYSTALS

Tb-doped SBN crystals were prepared by the Czochralski technique. Their dielectric, ferroelectric, and pyroelectric properties were studied. A low temperature phase transition between two polar phases was revealed by the anomalies of the dielectric and pyroelectric properties; the polar axis changes its direction during this transition. The point group of the low temperature phase may be mm2, m or 1.