Design of a continuously tunable delay line using vectorial modulational instability and chromatic dispersion in optical fibers

Abstract

International audienceWe design an all-optical tunable delay line based on both dispersive and wavelength conversion stages involving modulational instability of a two-frequency pump field propagating in a highly birefringent fiber. More precisely, we numerically show that, by varying the frequency separation between the two orthogonally polarized pump waves, we achieve a controllable and continuous delay of hundreds of picoseconds for signal pulse durations from picoseconds to nanoseconds, without pulse distortion and with only small peak power fluctuations. The proposed method does not require any tunable bandpass filter and can be applied to delay digital data streams at tens of Gbit/s depending on the pump power level

Influence of the pump shape on the modulation instability process induced in a dispersion-oscillating fiber

“…11(a1) and 12(a)]. We should emphasize that the present physical mechanism that introduces a relative time delay of the frequency-converted pulses strongly differs from the usual delay-line schemes that are associated with combining parametric wavelength conversion and dispersion [25,26] or from the scheme taking advantage of soliton fission in a DOF [23,24]. When compared with many fiber-based slow-light devices [27], our approach has the advantage that the tuning of the temporal delay is immune to any significant variations of the peak power of the pulse pair.…”