Acoustic propagation in the orientational glass K_0.95Li_0.05TaO₃

Abstract

Data are presented for the real and imaginary parts of the elastic susceptibility in KTaO3:Li. A frequency range of 107 Hz ≥ f ≥ 109 Hz and a temperature range 50 K ≥ T ≥ 120 K is covered. The data are interpreted in terms of Debye relaxation and a comparison with dielectric data on the same crystal reveals that the mechanism of relaxation are 90° flips of off-centre Li ions within off-centre sites. This finding extends the range of glass-like properties to concentration up to 5 %. © 1992, Taylor & Francis Group, LLC. All rights reserved.