Abstract : The work carried out during this PhD focus on the fabrication and the investigation of an InP-based saturable absorber (SA) device for high bit rate all-optical reshaping. The principle of operation of this all-optical and passive device is based on the non-linear absorption of quantum well (QW) suitably inserted inside a Fabry-Perot microcavity. Besides its polarisation-insensitive operation and its response time compatible with the futures high bit rate signals, the SA device may process several wavelength simultaneously thanks to its large bandwidth, making it as a promising candidate for future low cost all-optical regenerator for high bit rate WDM links.
Due to an optimised structure, we were able to make a device with a response time as short as the picoseconde and with a saturation fluence of only a few µJ/cm2. The experimental results allowed us to validate the SA-based microcavity autosaturation model developed during this work, as well as the one describing the SA device working at high bit rate by taking into account the important thermal effects.
Thanks to its optimisation and to a better management of the thermal effect, we were able to demonstrate for the first time the extinction ratio enhancement of a 160 GHz signal (+6 dB on 8 nm bandwidth) and the reshaping of a 160 Gbits/s signal with a SA device. Finally, 2R regeneration results got from a recirculating loop experiment at 10 Gbits/s and 43 Gbits/s are also presented and show a factor enhancement of the propagation distance of 9.5 (on 13 nm) and of 6 respectively.