Alexandra G. Grandpierre

Theory of stimulated Raman scattering cancellation in wavelength-division-multiplexed systems via spectral inversion

By exploiting the reflection symmetry of the underlying evolution equations, we theoretically demonstrate that stimulated Raman scattering crosstalk in continuous-wave wavelength-division-multiplexed systems can be totally eliminated using spectral inversion techniques. We show that this result is always true, irrespective of the shape of the Raman gain curve or the loss/gain profile along the optical fiber system. These results are illustrated by means of relevant examples.

Coherence enhancement of spatially incoherent light beams through soliton interactions.

We show that the spatial coherence of a partially incoherent light beam can be greatly enhanced through an energy-conserving interaction with an incoherent or a coherent dark spatial soliton. Computer simulations show that during this process a portion of the incoherent beam is trapped within the dark notch of the dark soliton, thus forming a sharp intensity spike. In this region the correlation length dramatically increases by at least 2 orders of magnitude.

Eliminating SRS channel depletion in massive WDM systems via optical filtering techniques

We demonstrate that the channel depletion due to stimulated Raman scattering in massive wavelength-division-multiplexed (WDM) systems can be eliminated using high-frequency pass filters. These filters, when inserted appropriately into the transmission link, can effectively suppress the SRS power flow from the WDM channels to lower frequency noise. Numerical simulations carried out on WDM systems indicate that the channel depletion penalties can be kept below 0.25 dB even for a total channel power of 2 W.

Stimulated Raman scattering crosstalk in massive WDM systems under the action of group velocity dispersion

We provide a theoretical model that can accurately describe the evolution of stimulated Raman scattering crosstalk in high-speed massive wavelength-division-multiplexed (WDM) systems. Our model takes into account channel walk-off effects due to group-velocity dispersion and directly involves the bit-1 probability and the duty cycle of the modulation sequence. Our analytical predictions are found to be in excellent agreement with numerical simulations carried out using pseudo-random bit patterns in a return-to-zero format. These results are also applicable even in the case of amplified WDM systems. Pertinent examples are provided.

Stimulated Raman scattering cancellation in wavelength-division-multiplexed systems via spectral inversion

We theoretically demonstrate that stimulated Raman scattering crosstalk in wavelength-division-multiplexed systems can be totally eliminated using spectral inversion techniques. This result is always true irrespective of the specific Raman loss/gain profile of the fiber system.

Stimulated Raman scattering threshold enhancement via optical filtering

We demonstrate that usage of a high frequency pass filter can enhance the stimulated Raman scattering threshold in an optical fiber. Our measurements performed in TrueWave optical fibers using a 1.7W pump at 1500nm indicate that, for a filter appropriately positioned in the fiber span, the maximum transmitted pump power can be increased by over 20% through suppression of the SRS noise.

SOLITARYLIKE RAMAN STATES IN MASSIVE WAVELENGTH-DIVISION-MULTIPLEXED SYSTEMS

We show that solitarylike stimulated Raman excitations are possible in massive wavelength-division-multiplexed fiber-optic systems. These self-similar states can propagate across channels at a constant rate that depends on the total power launched in the system and the waves spectral width. The evolution of these excitations under the action of noise and during collisions is investigated in detail.