All-optical 2R regeneration with a vertical microcavity based saturable absorber

Laurent Bramerie (1) , Quang Trung Le (1) , Mathilde Gay (1) , Arthur O'Hare (2) , Sebastien Lobo (1) , Michel Joindot (1) , Jean-Claude Simon (1) , H. T. Nguyen (3) , Jean-Louis Oudar (3)

1 FOTON - Fonctions Optiques pour les Technologies de l'informatiON
2 School of Physics
3 LPN - Laboratoire de photonique et de nanostructures

This paper gives an overview of recent demonstrations of optical 2R regeneration achieved by vertical microcavity mirror based multiple-quantum-well Saturable Absorber (SA). The potential of the device to perform WDM regeneration is firstly demonstrated through the first pigtailed saturable absorber chip implemented with 8 independent fibres using a cost effective coupling technique. The cascadability and wavelength tunability assessment of this module associated to a power limiter fibre-based function has been experimentally demonstrated at 42.6 Gbit/s. Because this method of power limiting is not a suitable solution for all-optical multichannel 2R regeneration, a new SA structure allowing a power limiting function was proposed. We describe and characterize such a structure in this paper. This new SA opens the door to a complete passive all-optical 2R regeneration relying upon a single technology, as shown in this paper through the use of two SA: SA.0 for extinction ratio enhancement and SA.1 for power level equalization allowing receiver sensitivity (up to 3.5 dB) and Q factor (up to 1.4 dB) improvement for a RZ signal at 42.6 Gbit/s. The limitation of SA.1 when the regenerator must be cascaded a large number of times is also described, leading to the observation that SA.1 should be more suitable for phase encoded formats which are more spectrally efficient than OOK formats. A SA.1 used as a phase-preserving amplitude regenerator in a 42.6 Gbit/s RZ-DPSK transmission system is therefore assessed. A fibre launched power margin of 2 dB and a receiver sensitivity improvement of 5.5 dB are obtained. Finally, we use, for the first time an SA.1 as a phase-preserving amplitude regenerator of RZ DQPSK signals. The regenerator is assessed in a recirculating loop at 28 Gbaud. The system tolerance to nonlinear phase noise is enhanced by 3 dB and the distance improvement factor was 1.3 for a BER=10-4.

Mots clés: All-optical regeneration; optical fiber communication; optical signal processing; saturable absorber

Domaines: Optique / photonique

Laurent Bramerie, Quang Trung Le, Mathilde Gay, Arthur O'Hare, Sebastien Lobo, et al.. All-optical 2R regeneration with a vertical microcavity based saturable absorber. IEEE Journal of Selected Topics in Quantum Electronics, 2011, 18 (2), pp.870. ⟨10.1109/JSTQE.2011.2125779⟩. ⟨hal-00721069⟩