We report here the first experimental observation of $N=3\mathrm{}$ solitonlike pulses generated by a passively mode-locked ring laser at 620 nm. The evolution of the pulse shape is recorded along the soliton period corresponding to about 2400 cavity round trips. Experimental indications of the soliton character of any pulse produced by this type of laser are also obtained. Properties of high-order solitons could offer new possibilities of intracavity pulse compression.

• Received 9 January 1986

DOI:https://doi.org/10.1103/PhysRevLett.56.1132