Phase composition, structure and transport characteristics of ZrO$_{2}$–Sc$_{2}$O$_{3}$ solid solution crystals additionally doped with Yb$_{2}$O$_{3}$

The effect of the co-doped Yb$_{2}$O$_{3}$ on the transport characteristics and stabilization of the cubic phase in solid solutions based on ZrO$_{2}$–Sc$_{2}$O$_{3}$ has been carried out (ZrO$_{2}$)$_{1-x-y}$(Sc$_{2}$O$_{3}$)$_{x}$(Yb$_{2}$O$_{3}$)$_{y}$ solid solution crystals, where ($x$ = 0.07–0.09; $y$ = 0.01–0.03), were grown by directional crystallization of the melt in a cold crucible. It is shown that crystals with a cubic fluorite structure were obtained at a total concentration of stabilizing oxides Sc$_{2}$O$_{3}$ and Yb$_{2}$O$_{3}$ above 10 mol%. Crystals with a total concentration of stabilizing oxides of 10 mol%, having a pseudocubic $t''$ -phase structure, at a fixed concentration of Sc$_{2}$O$_{3}$, have the maximum conductivity. It is shown that an increase in the Yb$_{2}$O$_{3}$ concentration in the field of cubic solid solutions leads to a decrease in the conductivity of the crystal. Crystals (ZrO$_{2}$)$_{0.9}$(Sc$_{2}$O$_{3}$)$_{0.09}$(Yb$_{2}$O$_{3}$)$_{0.01}$ have the maximum conductivity in the entire temperature range.