Fig. 4: A comparison between experimentally observed dispersive spectrum in a graded-index and a step-index multimode fiber.
From: General theory and observation of Cherenkov radiation induced by multimode solitons
A comparison between dispersive waves (DWs) generated in a step-index multimode fiber (MMF) (blue curve) and a parabolic-index MMF (green curve). The step-index MMF had a length of 10 m, a core diameter of 105 µm and a numerical aperture NA = 0.22. In both cases the extent of the DW spectrum is approximately the same. However, the DWs generated from a step-index MMF do not have the comb-like features, a signature of parabolic MMFs.
