Macroscopic quantum fluctuations in high-gain optical amplifiers

Abstract
We use numerical methods to investigate stochastic and coherence properties of the fields transverse profiles in stimulated Raman scattering. In the linear regime with diffractive coupling, the amplified signal is characterized by fluctuations that are macroscopic. We find an interesting dependence of the beam-pointing fluctuations on photon conversion efficiency. Our results for the linear regime compare well with recent experiments, and we report an increase in beam-pointing fluctuations in the nonlinear regime. We discuss the results of modeling with one and two transverse dimensions.