Raman gain calculation by Raman threshold study in telecom fibers

Abstract

A simple experimental configuration for measurement of the Raman gain coefficient is demonstrated. The Raman threshold condition plays a role important to calculate the critical power and the Raman gain coefficient. Analysis of the Raman threshold for second Stokes shows that the Raman gain coefficient scales with the inverse of the pump wavelength and the fiber attenuation, the obtained values are approximate to several quantities previously reported. With those physical properties the single pass evolution of pump and Stokes beams equations are simulated for different fiber lengths and several coupled pump powers. The numerical simulations show that the fibers losses and the numerical aperture play a predominant role in the Stokes generation. These results allow designing optical fibers efficient and/or poor in the Stimulated Raman scattering generation.