Abstract

In the past few years, non-classical states of light have been experimentally generated in various circumstances, but so far only with a low average number of photons per mode. We report here on the observation of an appreciable reduction of the intensity noise below the shot noise level on laser-like, high intensity beams generated by parametric interaction. In parametric down-conversion, a non-linear crystal pumped at frequency Ω_O generates two strongly correlated fields at frequencies Ω₁ and Ω₂, with Ω_O = Ω₁ + Ω₂ ("twin photon generation"). The crystal is inserted in an optical cavity resonant at frequencies Ω₁ and Ω₂, and pumped above the oscillation threshold.

© 1988 Optical Society of America