Physical-layer key distribution using synchronous complex dynamics of DBR semiconductor lasers
Anbang Wang,
Yicheng Du,
Qingtian Li,
Longsheng Wang,
Zhiwei Jia,
Yuwen Qin,
Yuncai Wang
Affiliations
Anbang Wang
Key Lab of Photonic Technology for Integrated Sensing and Communication, Ministry of Education, Guangdong University of Technology, Guangzhou 51006, China
Yicheng Du
Key Lab of Advanced Transducers and Intelligent Control System, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
Qingtian Li
Key Lab of Advanced Transducers and Intelligent Control System, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
Longsheng Wang
Key Lab of Advanced Transducers and Intelligent Control System, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
Zhiwei Jia
Key Lab of Advanced Transducers and Intelligent Control System, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
Yuwen Qin
Key Lab of Photonic Technology for Integrated Sensing and Communication, Ministry of Education, Guangdong University of Technology, Guangzhou 51006, China
Yuncai Wang
Key Lab of Photonic Technology for Integrated Sensing and Communication, Ministry of Education, Guangdong University of Technology, Guangzhou 51006, China
Common-signal-induced synchronization of semiconductor lasers with optical feedback inspired a promising physical-layer key distribution with information-theoretic security and potential in high rate. A significant challenge is the requirement to shorten the synchronization recovery time for increasing the key rate without sacrificing the operation parameter space for security. Here, open-loop synchronization of wavelength-tunable multi-section distributed Bragg reflector lasers is proposed as a solution for physical-layer key distribution. Experiments show that the synchronization is sensitive to two operation parameters, i.e., currents of grating section and phase section. Furthermore, fast wavelength-shift keying synchronization can be achieved by direct modulation on one of the two currents. The synchronization recovery time is shortened by one order of magnitude compared to close-loop synchronization. An experimental implementation is demonstrated with a final key rate of 5.98 Mbit/s over 160 km optical fiber distance. It is thus believed that fast-tunable multi-section semiconductor lasers open a new avenue for a high-rate physical-layer key distribution using laser synchronization.
