Evolution of guided modes under spatiotemporal perturbations

A general formalism for an optical guided mode in waveguides with periodically spatial and temporal perturbed boundaries is developed. A given mode propagating within such a waveguide is scattered in the general case into space-time harmonics. It is shown that the dynamic aspect of the modulation allows us to control the spectral response of the system as well as the line-shape of its resonances. Such a system offers interesting new possibilities for future electronic-optical hybrid devices where the temporal modulation is activated electronically. We validate our theoretical model using finite difference time domain (FDTD) simulations and demonstrate a potentially applicable electronically controlled optical modulation device.