Continuous-Wave Self-Oscillation Using Pair Production of Photons in Four-Wave Mixing in Sodium

Abstract

An oscillation is observed when a sodium cell interacting with two counterpropagating pump beams is placed inside a Fabry-Perot cavity. We have shown that, in our experimental conditions, this self-oscillation comes from a pair production of photons in degenerate four-wave mixing. We have found that self-oscillation occurs with a single passage gain equal to 1% even when the transmission losses through the mirrors are 6%.