J. Phys. Colloques
Volume 42, Numéro C6, Décembre 1981International Conference on Phonon Physics
|Page(s)||C6-456 - C6-458|
J. Phys. Colloques 42 (1981) C6-456-C6-458
THE EFFECT OF LATTICE STRAINS ON THE ACOUSTIC RELAXATION LOSSES IN DIELECTRIC CRYSTALS DUE TO MAGNETIC IONSP.J. King
Department of Physics, University of Nottingham, University Park, Nottingham NG7 2RD, England
Recently information on the lattice strains present at Fe2+ sites in KMgF3 has been obtained from electron spin resonance linewidth data. The use of this data in an empirical model previously used with success on Fe2+ : MgO shows that this model also gives an excellent description of the acoustic relaxation losses in Fe2+ : KMgF3. In order to place this empirical model on a more sound theoretical footing a theory of relaxation losses in multi-level systems based on the rate equations for the population of each level has been studied. The empirical model results only if simplifying assumptions are made and the implications of these are described.