Field fluctuations produced by parametric processes in fibers

In this report, the optical field fluctuations produced by four-wave mixing processes in fibers are studied in detail. Modulation interaction and phase conjugation amplify input signals, whereas Bragg scattering frequency-converts an input signal. If the input states are coherent, the quadrature fluctuations associated with the output states have Gaussian statistics. Formulas are derived for the quadrature means, variances and correlations, which are valid for arbitrary pump-induced coupling and dispersion- and pump-induced mismatch coefficients. The results of this report are relevant to communication systems and quantum-information protocols based on continuous variables.