ON/OFF phase shift keying for chaos-encrypted communication using external-cavity semiconductor lasers

• Published in: IEEE journal of quantum electronics Vol. 38; no. 9; pp. 1162 - 1170
• Main Authors: Heil, T., Mulet, J., Fischer, I., Mirasso, C.R., Peil, M., Colet, P., Elsasser, W.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-09-2002; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Chaos theory; Chaotic communication; Fiber lasers; Frequency synchronization; Laser feedback; Lasers; Mathematical models; Optical coupling; Optical feedback; Optical receivers; Optical transmitters; Phase shift keying; Semiconductor lasers; Synchronism; Synchronization
• ISSN: 0018-9197; 1558-1713
• DOI: 10.1109/JQE.2002.801950

Synchronization phenomena of two chaotically emitting semiconductor lasers subject to delayed optical feedback are investigated. The lasers are unidirectionally coupled via their optical fields. Our experimental and numerical studies demonstrate that the relative optical feedback phase is of decisive importance: a characteristic synchronization scenario evolves under variation of the relative optical-feedback phase mediating cyclically between chaos synchronization in conjunction with coherent fields, and uncorrelated states in conjunction with incoherent fields. As a key result, we propose, and numerically demonstrate, a novel ON/OFF phase shift keying method opening up new perspectives for applications in communication systems using chaotic carriers.