Abstract:
This review paper summarizes a new analytical approach to the theory of waves in periodic media developed in relation with the problems of fiber optics. An adequate definition of the oscillation phase, used as an independent variable, allows us to construct an infinite set of exact solutions describing excitation and damping of parametric oscillations, beyond perturbation theory.
Key words and phrases:linear oscillator, phase parameter, exact solution, parametric resonance, waves in periodic media, Bragg waveguide.