In this work, we have experimentally investigated the generation of broadband Optical Frequency Comb (OFC) based on a gain-switching Vertical-Cavity Surface-Emitting Laser (VCSEL) driven by different modulation signals (including triangular-current, sinusoidal-current and square-current) under optical injection. For such a system, various modulation signals are first used to drive the VCSEL into the gain-switching state, and then an external optical injection is further introduced into the gain-switching VCSEL to generate broadband OFC. The experiment results show that the OFC output from the square current modulated VCSEL subject to optical injection has better performance compared to other two modulation signals. Driven by square signal with matched operation parameters, a high-quality OFC can be acquired, with stable comb lines, high coherence, wide bandwidth of 72.0 GHz within 10 dB amplitude variation and low single sideband phase noise at the fundamental frequency below −113.3 dBc/Hz at 10 kHz.
KEYWORDS: Microsoft Foundation Class Library, Modulation, Signal to noise ratio, Semiconductor lasers, Microwave radiation, Laser optics, Frequency combs, Picosecond phenomena, Optoelectronics, Nonlinear dynamics
Based on a current modulated semiconductor laser (SL) subject to optical injection, tunable and broadband microwave frequency comb (MFC) generation is theoretically investigated. For a SL under only current modulation, a seed MFC with relatively narrow bandwidth can be generated. Then, an optical injection is introduced to improve the quality of seed MFC. Furthermore, the influences of operation parameters on the performance of MFC are also discussed. The numerical results show that after introducing optical injection with injection coefficient k = 1.8×10-4 and detuning frequency Δf = 6.0 GHz, the MFC bandwidth can be further increased by 15.6 GHz and the signal-to-noise ratio can be improved by more than 20 dB.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.