Stokes-to-Stokes and anti-Stokes-to-Stokes energy transfer in a Raman fibre laser under different cavity configurations

We report an experimental study of the signals delivered by a Raman fibre laser under different output coupling conditions. Our main results allow us to conclude that feedback reflectivity variations influence Stokes energy-transfer mechanisms. We also confirmed that in low-feedback systems high conversion efficiencies imply high thresholds for Stokes generation, whereas the contrary occurs for high-reflective output cavities. (paper)