Slow-light regime and critical coupling in highly multimode corrugated waveguides

Hamza Kurt (1) , Henri Benisty (1) , T. Melo (1) , Omer Khayam (1) , Cyril Cambournac (1)

1 Laboratoire Charles Fabry de l'Institut d'Optique / Naphel

Large and periodically corrugated optical waveguide structures are shown to possess specific modal regimes of slow-light propagation that are easily attainable. The very multimode nature of the coupling is studied by employing coupled-mode theory and the plane-wave expansion method. Given a large enough light cone, associated with a surrounding medium with low enough refractive index, we notably identify a critical slowdown regime with an interesting bandwidth-slowdown product. Essential features of these original systems are further explored: the nature of the coupled modes, the role of gain, symmetry effects, polarization, and relation with photonic-crystal systems. Practical systems are introduced using finite-difference time-domain methods, which provides first-order rules for the use of the above phenomena and their implementation in devices

Domaines: Optique [physics.optics]

Hamza Kurt, Henri Benisty, T. Melo, Omer Khayam, Cyril Cambournac. Slow-light regime and critical coupling in highly multimode corrugated waveguides. Journal of the Optical Society of America B, 2008, 25 (12), pp.C1. ⟨hal-00573058⟩