Single Crystal Growth and Electrical Properties of Lanthanum- and Gadolinium-Doped BaTiO₃

Abstract

Single crystals of (Ba_0.96-xLn_xSr_0.04)TiO₃ (Ln=La, Gd) were grown over a composition range of x=0.001 to 0.03. Electrical resistivities of the single crystals were measured by the DC four-probe method. The temperature dependence of resistivities of these crystals changed from semiconductive to metallic at the Curie temperature (T_C). Although the room temperature resistivities of Gd-doped single crystals were independent of Gd concentration of 1 to 3%, they decreased monotonically with increasing the dopant concentration after annealing in a reducing atmosphere.