We experimentally demonstrate that two chaotic passive Q-switched lasers can be synchronized by modulating the saturable absorber in the cavity of one laser with the output of the other laser. The entrainment of the chaotic motion takes place when the slave system has a slightly different strange attractor from that of the master system. The observed synchronized pulsation of the two lasers is well reproduced by the computer simulation based on our rate-equation model.

• Received 9 November 1993

DOI:https://doi.org/10.1103/PhysRevLett.72.3502