The experimental results of the reflection at a MgF_(2) waveguide between Ag metallic walls and the light scattering from the same system for p and s linearly polarized incident light are reported. The thickness of the dielectric film was chosen in such a way that the system supports six transverse magnetic and six transverse electric-guided modes at a given wavelength. We found dips in the reflection as a function of the incident angle as well as a function of the wavelength that are due to excitation of modes in the MgF_(2) film. From the spectral reflection curves the dispersion relation of the modes is obtained. The scattered light shows peaks at angles corresponding to the measured excitation of the waveguide modes. These peaks are because of single-order scattering and occur at any angle of the incident light. Enhancement peaks in the scattering response are found in resonant conditions, and the efficiency of injecting light into the guide is reduced.
展开▼
