Crystal growth and properties of a new member of Pb-K-niobate series

Abstract

A new member in the tungsten-bronze family of ferroelectric lead-potassium-niobate (PKN), with general formula Pb_1-xK_2xNb₂O₆, has been grown as bulk single crystal. Growth of PKN with charge composition x = 0.23 has been achieved using the Czochralski technique of crystal pulling. Large diameter boules were grown in platinum crucibles at temperatures between 1280 °C and 1300°C. Crystallographic studies were conducted using X-ray diffraction techniques. The samples were characterized for ferroelectric properties between 25 °C and 600 °C and for optical absorption. This paper presents the crystal synthesis and the results of ferroelectric and optical characterization.