Statistical properties of polarisation dependent gain in fibre Raman amplifiers

Scaling of the raman gain coefficient: applications to germanosilicate fibers

“…This averaging is implicitly assumed in the remainder of this text. The force is thus given by (20) When the total electric field interacting with the oscillator is the sum of the pump and the scattered field, the driving force at frequency originates from products containing the electric field at the pump and signal frequency, i.e., . The relevant relation between the th component of the force and the electromagnetic field is then (21) where and are the components of the vectors and , respectively.…”

“…This difference between cross and parallel coupling leads to polarization-dependent gain (PDG) in Raman amplifiers when the pump light has a high degree of polarization. The effect can be particularly large when the signal and pump light copropagate in the fiber [19], [20]. PDG can be significantly reduced by either depolarizing the Raman pumps with, for example, a Lyot depolarizer [21] or by using pairs of uncorrelated polarized pumps that are multiplexed with a polarization-beam combiner.…”

Raman Amplification: An Enabling Technology for Long-Haul Coherent Transmission Systems

“…Content may change prior to final publication. statistically coupled during propagation [24], [25] resulting in a Gaussian distribution in gain for low PMD fiber. There will be a larger variation in gain due to PDG in the forward Raman case compared to backward Raman [24].…”

“…statistically coupled during propagation [24], [25] resulting in a Gaussian distribution in gain for low PMD fiber. There will be a larger variation in gain due to PDG in the forward Raman case compared to backward Raman [24]. For dual-polarized signals, the gain compression in forward Raman is also polarization dependent such that higher gain along one polarization state will result in higher pump depletion which has the effect of reducing the difference in pump power between each polarization state.…”

Polarization-Related Statistics of Raman Crosstalk in Single-Mode Optical Fibers

“…The effects of PMD on SRS have been extensively studied in the context of RA both experimentally [28]- [31] and theoretically [32], [33]. Note that results for RA with the undepleted pump assumption can be reused for the context of RXT with the un-filled probe assumption just swapping RA gain with RXT loss.…”