Spatial Fourier analysis of modes at the output of a homogeneous restricted system of coupled waveguides

The propagation of light in restricted homogeneous systems of tunnel-coupled waveguides is studied. The Fourier analysis of modes at the output of the waveguide system depending on the end-excitation angle of waveguides revealed the region of excitation angles corresponding to excitation of Bragg modes. The expressions for the Bloch vector for a great number of separate waveguides are presented which describe the reflection of light in a periodic layered medium. It is shown that the Bragg diffraction of light waves in film lasers can considerably change their radiation parameters.