J.V. Harzer, B. Hillebrands, et al.
Journal of Magnetism and Magnetic Materials
The soft-mode damping and the ultrasonic attenuation at a displacive phase transition has been calculated with the help of a model Hamiltonian. The soft-mode damping parameter Γ is finite at the transition temperature, whereas the ultrasonic attenuation α is singular. For sound frequencies ωΓ, the ultrasonic attenuation is proportional to the sound frequency squared with critical exponents η=0.5 and 1.5, respectively, for weakly damped and strongly overdamped soft-mode frequencies. A comparison is made with previous calculations based on the Silvermann model. © 1970 The American Physical Society.
J.V. Harzer, B. Hillebrands, et al.
Journal of Magnetism and Magnetic Materials
J.K. Gimzewski, T.A. Jung, et al.
Surface Science
S.F. Fan, W.B. Yun, et al.
Proceedings of SPIE 1989
J.H. Kaufman, Owen R. Melroy, et al.
Synthetic Metals