Spin-Lattice Relaxation Effects in Critical Sound Propagation

• Authors: A. Pawlak
• Languages of publication: EN

Abstracts

EN

The nonasymptotic critical properties of sound propagation are studied in compressible Ising system above T_{C}. In the present paper we analyse a model where in addition to the coupling to two order-parameter fluctuations the sound mode couples linearly to the fluctuations of spin-energy and lattice-energy densities. Both subsystems exchange energy with the rate determined by the bare spin-lattice relaxation time. The total energy may be conserved or not. The crossover between insulator-like behaviour ~t^{-2α} and metal-like behaviour ~t^{-(zν+α)} in ultrasonic attenuation is investigated according to the value of ultrasonic frequency, the reduced temperature t, bare relaxation times and various coupling constants.

Keywords

EN

62.65.+k; 05.70.Jk

• Journal: Acta Physica Polonica A
• Year: 1997
• Volume: 92
• Issue: 2
• Pages: 449-452

Dates

published

1997-08

Contributors

author

A. Pawlak

• Institute of Physics, A. Mickiewicz University, Matejki 48/49, 60-769 Poznań, Poland