Transition from crystal-like to glass-like behavior of thermal conductivity in the Sr0.16Ba0.54La0.30F2.30 solid solution

Abstract

Using a steady-state axial flow technique, we have measured the thermal conductivity of single crystals of congruently melting SrF2-BaF2-LaF3 solid solutions from 50 to 300 K: Ba0.66Sr0.34F2 (minimum in the melting curves), Ba0.70La0.30F2.30 (maximum in the melting curves), and Sr0.16Ba0.54La0.30F2.30 (saddle point on the melting surfaces). The thermal conductivity of the isovalently doped fluorite solid solution is typical of crystals containing point defects. Heterovalent substitution leads to glass-like behavior of thermal conductivity.