Effect of Nd+3 and K+ Substitutions on Phase Transition of Ferroelectric lead Germanate Single Crystals
نویسنده
چکیده
Double doped (Nd + K) ferroelectric lead germanate single crystals were grown by controlled cooling of melt. Greenish tinge crystals of 5 x 4 x 3 mm were found embedded in the solid. Pure lead germanate was grown by cz technique for comparative analysis. Dielectric constant and loss tangent of pure crystals showed a sharp dielectric peak at 179°C while dielectric constant of doped crystals showed temperature dependence with diffuse dielectric maxima at 350°C. Results suggest a significant positive shift of ferroelectric transition temperature by 171°C. Mechanisms for the shift in transition temperature and diffuse nature of dielectric maxima are discussed.
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