Applications of semiconductor lasers to secure communications

We numerically study the synchronization of two chaotic semiconductor lasers in a master-slave configuration. To synchronize the lasers a small amount of the output power from the master laser is injected into the slave laser. We show that the output of the master laser can be used as a chaotic carrier to encode a digital message which can be recovered at the receiver. We also check the quality of the synchronization diagram when the two lasers are slightly different.