Description of the Gaussian beam excited surface wave

The problem of excitation of surface wave at the interface between two dielectric media is not new. During the last few years the topic concerning the creation of a new type charged particles accelerator, which uses laser radiation has become very popular. For the operation of such devices, the possibility of transforming the beam radiation field into a surface wave field must be investigated. There are several theoretical models describing this problem. We use the Fourier transform technique for the incident and refracted wave. The geometry that is considered is that of a Gaussian beam incident upon the interface separating two dielectric half-spaces. When the angle of incidence of the beam is greater than the total internal reflection angle, the surface wave will appear under the upper medium. We present the Gaussian beam as a integral over the plane wave spectrum. Adding the Fresnel coefficient to the reflection or refraction of the plane waves and using the corresponding boundary conditions, we obtain the field of the reflected or refracted wave