The thermal transport properties of solid solution (LaxGd1−x)2Zr2O7 were investigated. The introduction of point defects was intended to provide extra phonon scattering, and a much lower thermal conductivity of the solid solution was obtained as compared with those of La2Zr2O7 and Gd2Zr2O7. The phonon mean free paths of the solid solution were estimated and analyzed with respect to the point-defect scattering effect. The Young's modulus and heat capacity of the solid solution, which determined the mean velocity and the energy carried by the phonons, respectively, were measured. Both exhibited a diminution when compared with the end- materials; due possibly to the lattice relaxation caused by point defects. A theoretical model, which contained no adjustable parameters, was presented that accurately described the thermal conductivities of the solid solution by taking account of the mass and strain-field fluctuations induced by point defects.

Effect of Point Defects on the Thermal Transport Properties of (LaxGd1−x)2Zr2O7 - Experiment and Theoretical Model. C.L.Wan, W.Pan, Q.Xu, Y.X.Qin, J.D.Wang, Z.X.Qu, M.H.Fang: Physical Review B, 2006, 74[14], 144109 (9pp)