Concepedia

Optical Power Handling Capacity of Low Loss Optical Fibers as Determined by Stimulated Raman and Brillouin Scattering

Applied Optics · 1972 · 1.1K citations · 7 references

TL;DR

The study defines a critical power below which stimulated Raman and Brillouin scattering can be ignored, given by \(P_{\text{crit}}\approx 20A\alpha/\gamma_0\), where \(A\) is the core area, \(\alpha\) the attenuation, and \(\gamma_0\) the gain coefficient. For low‑loss fibers (20 dB/km, \(10^{-7}\) cm² core), the critical power is about 35 mW for Brillouin scattering and roughly 100 times higher for Raman, underscoring that these stimulated effects must be accounted for in optical communication system design.

Abstract

The effect of stimulated Raman and Brillouin scattering on the power handling capacity of optical fibers is considered and found to be important especially when low loss optical fibers are used. A critical power below which stimulated effects may be neglected is defined for forward and backward Raman scattering and for backward Brillouin scattering. This critical power is determined by the effective core area A, the small signal attenuation constant of the fiber alpha, and the gain coefficient for the stimulated scattering process (gamma0), by the approximate relation P(crit) approximately 20Aalpha/(gamma0). For a fiber with 20-dB/km attenuation and an area of 10(-7) cm(2)P(crit) approximately 35 mW for stimulated Brillouin scattering. For stimulated Raman scattering P(crit) is approximately two orders of magnitude higher. It is concluded that these effects must be considered in the design of optical communication systems using low loss fibers.