Enhancement of the stability of a synchronously excited cw dye laser by insertion of a nonlinear absorber

An experimental investigation was made of combined mode locking of a cw laser utilizing a mixture of rhodamine 6G (amplifier) and malachite green (absorber). The action of a saturable absorber shortened the output pulses to 700 fsec, widened the range of existence of the short pulses, and appreciably increased the lasing stability compared with synchronous excitation of pure rhodamine 6G. These characteristics of the radiation of a laser with combined mode locking were associated with the saturation dynamics of the gain and the absorption.