Abstract

We report huge pulsating instabilities in a single mode homogeneously broadened Raman laser. Ruelle-Taken, intermittent and period-doubling routes to chaos are observed. The laser, which uses NH₃ as the active medium near-resonantly pumped on the aR(6,0) transition by a CO₂ laser, emits on aP(8,0) transition at ~ 12.8 μm. This lasing transition has recently been clearly identified as Raman in origin for NH₃ pressures 1 - 20 torr and pump intensity ~ 600 kW/cm² (operating conditions for our experiment) and possesses extremely high gain ~ 10% cm⁻¹ [1].

© 1985 Optical Society of America