Exact Reflection Coefficients Research Articles

Transmission and reflection of surface waves at a corner: 1. Love waves

Approximate reflection coefficients have been obtained by a Green's function technique for Love waves normally incident upon the corner of a wedge formed by two stress-free planes. The incident waves travel in a layered medium with structure parallel to one of the faces of the wedge. The approximation yields the exact reflection coefficient for wedge angles of π and π/2.

Theory of transverse waves in Vlasov-plasmas: III. Reflection of electromagnetic waves by a plasma half-space

In this paper we solve the problem of reflection of normally incident electromagnetic waves by a plasma half-space. The equilibrium plasma is supposed to be spatially homogeneous and isotropic in velocity space; the particles are assumed to be reflected specularly at the plane boundary. From the multitude of stationary solutions, compatible with the latter assumption, one is selected by imposing a causality condition. The exact reflection coefficient found from this solution is compared with the results predicted by the Fresnel formula with the aid of the refractive index; the present problem leads to a natural extension of the definition of the refractive index, given in I, to the range of frequencies smaller than the plasma frequency. The relation to the theory of the anomalous skin effect in metals is also discussed.

Test of the Validity of a Shell Theory for the Reflection of Sound from Thin Shells

In 1943 Epstein introduced a method for obtaining differential equations for the deformations in an elastic shell. This method only requires assumptions concerning the thickness of the shell and the analytic properties of the deformation and stress components. Earlier methods involve additional assumptions. In 1953 Kennard reformulated the Epstein method in a more standard form and included the possibilities of nonvanishing boundary conditions for the components of stress. Using the method in the original Epstein approach, but including non-zero boundary conditions, the author has obtained an expression for the amplitude of a plane wave incident on an infinite plate immersed in a fluid. The results have been found to be identical with the exact reflection coefficient in the limit kd≪1, where k is the wave number of a transverse wave in the plate and d is the thickness of the plate. Details of the development will be presented.