2023-06-18
浏览次数：433Title: External Cavity Modes for Laser Dynamical：Photonic Microwave Generation
Prof. Nelson Sze-Chun Chan (陳仕俊)
Professor, Department of Electrical Engineering
City University of Hong Kong, Hong Kong, China
Abstract: Semiconductor lasers exhibit a wide variety of nonlinear dynamics for photonic microwave generation. In this presentation, some recent progress will be discussed on the generation of square-wave switching, adiabatically modulated oscillations, and high-dimensional chaos. Based on the mechanisms of external cavity modes (ECMs), square-wave switching between stable and unstable microwave oscillations is theoretically analyzed. Through reconciliation of the equation-of-motion and frequency-gain plane ellipses, the switching period expansion time is theoretically obtained to explain a long-standing issue related to quasi-periodicity. Then, based on adiabatic modulation, microwave frequency-modulated continuous-wave (FMCW) generation is experimentally achieved on an optical carrier. The approaches employ two injected lasers, thereby quadrupling the subcarrier to a millimeter-wave frequency of 80 GHz with a sweep range of 6 GHz. Inherent competition between external locking and frequency modulation is revealed about locking the whole comb. Additionally, the correlation dimension associated with optical chaos under feedback is thoroughly evaluated. The experimental data of large sizes enable a careful quantification of the dimension beyond 10, which is amongst the highest values reported.
Biography: Nelson Sze-Chun Chan (陳仕俊) received the B.Eng. degree in electrical and electronic engineering from the University of Hong Kong, Hong Kong, China, in 2001, and the M.S. and Ph.D. degrees in electrical engineering from the University of California at Los Angeles (UCLA) in 2004 and 2007, respectively. He is currently a Professor in the Department of Electrical Engineering and the State Key Laboratory of Terahertz and Millimeter Waves at the City University of Hong Kong, Hong Kong, China. His research interests include nonlinear dynamics of semiconductor lasers, optical chaos generation, radio-over-fiber, and photonic microwave generation.
2023年6月21日（周三）15:30-16:00
逸夫科学馆二楼报告厅, 华南理工大学五山校区
欢迎广大师生参加！