Key points are not available for this paper at this time.
Measurements of the specific heat, thermal conductivity, dielectric constant and thermal expansion of the single-crystal fast-ion conductor (Zr{O₂) }₁-ₗ ({Y₂O₃) }ₗ with x=0. 10, 0. 16, and 0. 18 exhibit behavior similar to that observed in amorphous solids and attributed to two-level states. The data can be fitted by the phenomenological tunneling states model, but at the expense of a more complex spectrum of two-level-state equilibration times than has generally been used for amorphous solids. The possible relationship of the two-level states with known defects is explored and found to be unsatisfactory.
Walker et al. (Tue,) studied this question.