Observation of Period Doubling in an All-Optical Resonator Containing NH3Gas

Abstract
Two-round-trip-time modulation of the cavity field has been observed in a passive ring resonator, containing an ammonia cell, pumped by smooth 100-ns CO2 laser pulses. The results are in excellent accord with the theory of Ikeda instability instability in a two-level system, which is generalized to include reservoir kinetics.