Communication with chaos using semiconductor lasers with an air gap

This paper reports the numerical results of the dynamical behavior of an integrated semiconductor laser subject to multiple optical feedback loops. The laser setup consists of a distributed feedback active section coupled to multi section cavities. It has been found that, due to the multiple feedback loops and under certain operating conditions, the laser displays chaotic behaviors appropriate for chaos-based communications. The optimal conditions and suitable parameters for chaos generation have been identified. The synchronization of two unidirectional-coupled (master–slave) systems has been studied. Finally, examples of high bit rate message encoding and decoding have been described and discussed.