Effects of Surface Irregularities on Single Crystal Resonance Parameters

Abstract

Measurements of ferromagnetic resonance line width, and anisotropy of line width of yttrium iron, garnet, and manganese zinc ferrite single crystals as a function of surface irregularities from 8 to 75 μ, and frequency from 2 to 16 kMc are presented. These measurements indicate that the frequency dependence of the line width and line width anisotropy in these materials for varying degrees of surface roughness can be interpreted with respect to spin wave scattering theories. In this case, the surface irregularities act as scattering centers for the uniform precession, causing a loss of energy into degenerate spin wave states with wavelengths corresponding to the size of the irregularities.