Dielectric grating with shift

One of the main type of guiding structures on the basis of linear isotropic materials are dielectric gratings. In this connection the problem of scattering on dielectric grating of either plane and volume waves was solved in the number of research works by either theoretical or numerical methods. Dielectric grating is a particular case of medium with periodically varying parameters, particularly with periodically changing permittivity. It would be interesting to see how some kind of a shift in parameters of periodical medium would influence its properties. We will solve the eigenvalue problem for the optical electromagnetic waves spreading through the structure consisting of equidistant dielectric layers, in case when thickness of some layer differs from the previous ones