Frederic Surre

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We investigate the power and the polarization dependence of the intraband dynamics in a bulk semiconductor optical amplifier using both a 2.5-ps pump-probe experimental set-up in contra-propagation and a theoretical model. Our model is based on the rate equations and takes into account the polarization dependence of the gain. By comparing experimental and(More)
The consequences of tailoring the longitudinal carrier density along the active layer of a multi-contact bulk semiconductor optical amplifier (SOA) are investigated using a rate equation model. It is shown that both the noise figure and output power saturation can be optimized for a fixed total injected bias current. The simulation results are validated by(More)
A free space contra-propagation set-up is implemented and a dynamic pump-probe study of the eigenmodes of a SOA in the picosecond regime is undertaken. The time-resolved probe transmission of the TE and TM modes of the device is measured for the co and cross-polarised cases as a function of pump pulse energy. The relative contributions of interband and(More)
This paper describes the design, commissioning, and evaluation of a fiber-optic strain sensor system for the structural health monitoring of a prestressed concrete posttensioned box girder railway bridge in Mumbai, India, which shows a number of well-documented structural problems. Preliminary laboratory trials to design the most appropriate sensor system(More)
and Landais: The use of polarization effects in semiconductor optical amplifiers to perform all-optical… ABSTRACT As the need for higher and higher bandwidths in telecommunication systems continues, it is widely predicted that at some point in the future optical processing will need to be performed all-optically. Several techniques have been proposed to(More)
The polarization dependence of gain dynamics in a bulk semiconductor optical amplifier has been investigated using a 2.5 ps pump-probe set-up in a counter-propagation configuration. A theoretical model based on the carrier density rate equation has been developed to simulate the experiment. Comparison of experimental and computational results highlights the(More)
In this paper we present some characterizations of passively mode-locked semiconductor lasers. These lasers are multimode and they exhibit a modulation of their output power even though they are DC-biased. The modulation frequency corresponds to their free-spectral range. We demonstrate their potential: for generation of ultra-fast modulation for THz wave(More)
The use of semiconductor optical amplifiers (SOA) in optical communications networks has so far been limited due to their inherent large noise figure (NF) compared to Erbium Doped Fibre Amplifiers. Therefore improvement of the noise performance of SOAs is critical to their widespread adoption in future networks. We propose to reduce the NF of the SOA by(More)
Although self pulsating (SP) lasers are DC biased, they feature a modulation of the output power. For the results presented in this paper, the SP frequency corresponds to the frequency spacing between longitudinal modes or its second harmonic. The performances of both a 40 GHz self pulsating distributed Bragg reflector laser and of a 660 GHz slotted laser(More)