The formation of a light field with suppressed photon fluctuations by nonlinear optical methods

A quantum theory is developed to describe optical parametric amplification under low-frequency pumping, which is observed in nonlinear photonic crystals in sequential interactions of light waves with multiple frequencies. Spatial variations of the mean number of photons and the Fano factor at signal and additional frequencies are analyzed. It is shown that a field with a sub-Poisson statistics of photons can be formed at a signal frequency which is 1.5 times higher than the frequency of pumping.