Spectral phase induced by the reflection on a mirror-based waveguide grating in the neighbourhood of modal resonance

Abstract

International audienceA linearly polarized plane wave impinging on a mirror-based waveguide grating is shown to experience a 2 pi phase shift of controllable slope in the reflection spectrum. Such a zeroth-order resonant grating effect is adequately confirmed by means of an ellipsometer. The close agreement between the analytical representation of grating coupled waveguide resonances with the experimental results confirms the relevance of the underlying phenomenological understanding of resonant gratings