This paper draws attention to the fact that point focus beam (PFB) V(z) curves of anisotropic solids are dominated by a small number of principal SAW rays, which are associated with directions in which Rayleigh and pseudo-SAW slownesses are stationary. This is explained on the basis of the complex mean reflectance function of the surface, i.e. the reflectivity R(θ,Φ) averaged over the azimuthal angle Φ, and also in terms of a ray model. This fact facilitates the extraction of materials information from PFB V(z) curves. The utility of PFB AM for anisotropic solids is illustrated using computed velocity and V(z) data for the Fe(001) surface and for Fe(001) with an overlayer of isotropic iron.
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