4. Nonlinear phenomena 4.1. Second-order nonlinear phenomena 4.2. Third-order nonlinear phenomena 4.3. Stimulated Raman scattering 4.4. Stimulated Brillouin scattering 4.5. Four-wave mixing (FWM) 4.6. Self-phase modulation (SPM) 4.7. Cross phase modulation (XPM) 4.8. Theoretical description of GVD phenomenon and self-phase modulation 4.8.1. Nonlinear Schrödinger equation 4.8.2. Inclusion of the...

This paper presents a thorough study of the different sources of noise affecting Brillouin optical time-domain analyzers (BOTDA), providing a deep insight into the understanding of the fundamental limitations of this kind of sensors. Analytical and experimental results indicate that the noise source ultimately fixing the sensor performance depends basically on the fiber length and the input pum...

Modulation instability can limit the resolution and the range of distributed fibre sensors based on stimulated Brillouin scattering. In this paper we analyse this process and suggest adequate methods to overcome it.

Three-dimensional wave propagation simulations and experiments show that the gain exponent, an often used metric to assess the likelihood of stimulated Brillouin scatter, is insufficient and must be augmented with another parameter, Nr, the ratio of the resonance length, Lres, to the laser speckle length. The damping rate of ion acoustic waves, ν, and thus Lres, which is proportional to ν, are ...

We demonstrated the superluminal propagation at negative group velocity using stimulated Brillouin scattering (SBS) in optical fibers. In the scheme, the Stokes wave is circulated back into the ring cavity for Brillouin lasing to enhance the peak loss. The experiment demonstrated the superluminal light propagation can be realized by increasing the input signal power. The largest time advancemen...

Numerical and experimental investigations of stimulated Brillouin scattering signal amplification in standard single-mode fibers under pump depletion show that while gains are reduced, the same orthogonal input states of polarization that provide maximum and minimum gain in the undepleted case practically continue to do so in the depleted regime. Using a scaled Brillouin gain coefficient, the p...