Sophie Borne

10.2 Tbit/s (256x42.7 Gbit/s PDM/WDM) transmission over 100 km TeraLight/sup TM/ fiber with 1.28 bit/s/Hz spectral efficiency

We demonstrate the transmission of 256 polarization-division and wavelength-division multiplexed channels at 42.7 Gbit/s rate over 100 km of TeraLight/sup TM/ fiber. An overall capacity of 10 Tbit/s is achieved in C and L bands at a record 1.28 bit/s/Hz spectral efficiency.

Transmission of 256 wavelength-division and polarization-division-multiplexed channels at 42.7Gb/s (10.2Tb/s capacity) over 3/spl times/100km of TeraLight/spl trade/ fiber

10.2Tb/s capacity is demonstrated over 3/spl times/100km in C and L bands, using 42.7Gb/s channels. The wavelength allocation was chosen while taking into account narrow optical filtering at the transmitter and receiver ends and second-order Raman pumping is used to improve the signal-to-noise ratio.

Transmission of 125 WDM channels at 42.7 Gbit/s (5 Tbit/s capacity) over 12/spl times/100 km of TeraLight/spl trade/ Ultra fibre

The transmission of 125 ETDM channels at 42.7Gbit/s (5 Tbit/s capacity) is demonstrated over 12/spl times/100 km of the new TeraLight/spl trade/ Ultra fibre. The result is obtained with VSB-like filtering at the receiver end and Raman-assisted erbium amplification over C and L bands.

Modeling of multiwavelength Raman fiber lasers using a new and fast algorithm

We describe a numerical model for a multiwavelength Raman fiber laser. It uses an original algorithm which makes the model robust and fast. We show a comparison between simulated and measured Raman laser output powers, characterized by their slope efficiency and their threshold.

RIN transfer in copumped Raman amplifiers using polarization-combined diodes

Pump-to-signal relative-intensity-noise (RIN) transfer in a forward-pumped Raman amplifier using polarization-combined diodes is measured and analyzed. For the first time, by means of experiment and simulations, we call attention to the impact of the polarized nature of stimulated Raman scattering on RIN transfer. We show that measuring the RIN at the output of a depolarized Raman pump and inserting this figure in the commonly used RIN transfer equation is not sufficient for good signal RIN prediction. Although depolarizing the Raman pump enables polarization-independent signal gain, proper modeling of RIN transfer should include the polarization dependence of the Raman effect and the polarization mode dispersion of the fiber.

320-Gb/s (32 x 10 Gb/s WDM) transmission over 500 km of conventional single-mode fiber with 125-km amplifier spacing

Thirty-two 10-Gb/s channels spaced by 100 GHz are transmitted over 500 km of dispersive fiber (D>+19 ps/nm/spl middot/km) with 125-km amplifier spacing. This is made possible by the use of 3 in-line dual-stage flat-gain erbium-doped fiber amplifiers (EDFAs) incorporating dispersion-compensating fiber. The transmission performance is significantly improved when a 9-km section of dispersion compensating fiber is added at the receiver end, for the longer-wavelength half of the multiplex.

3.2 Tb/s (80 /spl times/ 40 Gb/s) C-band transmission over 3 /spl times/ 100 km with 0.8 bit/s/Hz efficiency

We demonstrate 50 GHz-spaced 80 /spl times/ 40 Gbit/s WDM transmission over 300 km of TeraLight/spl trade/ fibre without polarisation demultiplexing, using the PSBT format. A record capacity of 3.2 Tbit/s is thus achieved over the C-band only, with a spectral efficiency of 0.8 bit/s/Hz.

Influence of polarization on pump-signal RIN transfer and cross-phase modulation in copumped Raman amplifiers

Pump-to-signal relative intensity noise (RIN) transfer in copumped Raman amplifiers is analyzed. By means of simulations and experiments, the authors call attention to the impact of the polarized nature of stimulated Raman scattering on RIN transfer. Although depolarizing the Raman pump enables polarization-independent signal gain, the authors demonstrate that proper modeling of RIN transfer requires including the polarization dependence of the Raman effect and the polarization mode dispersion of the fiber. A second key phenomenon is emphasized. Besides the RIN transfer induced by Raman gain, pump RIN is also transferred to the signal via nonlinear gain. This phenomenon can be addressed as pump-signal cross-phase modulation since it essentially generates phase noise on the signal. For the first time, in this paper, a model of pump-to-signal RIN transfer that includes polarization and nonlinear gain is presented. The authors reveal the key influence of these factors that had been uncared for so far. Their analysis is supported by experimental data. Signal noise characteristics (RIN spectrum and high-resolution optical power spectrum) measured at the output of a copumped Raman amplifier were presented. The Raman pump is a pair of semiconductor diodes in the first two experiments and then a Raman fiber laser. For these two kinds of depolarized or unpolarized Raman pumps that are commonly used in the field, the authors emphasize the necessity of considering polarization for the good assessment of RIN transfer

Dependence of fiber Bragg grating thermal stability on grating fabrication process

Summary form only given. Fiber gratings thermal stability was investigated at 600/spl deg/C during 600 hours. These results point out the strong dependence of gratings thermal stability on their fabrication process, different defects may be created and different mechanisms involved, as well as the complexity of their long-term evolution law, which will have to be fully understood before deriving grating lifetime under operating conditions.

FWM-assisted Raman laser for second-order Raman pumping

By enabling four-wave-mixing process within the cavity, a new type of Raman fiber laser for second-order pumping applications is demonstrated, exhibiting high stability down to a few milliwatts for the seed (1428 nm).