Frequency-Tunable Broadband Microwave Comb Generation Using an Integrated Mutually Coupled DFB Laser
Wu Zhao, Yuanfeng Mao, Yaobin Li, Guangcan Chen, Dan Lu, Qiang Kan, Lingjuan Zhao
Abstract
A microwave frequency comb (MFC) generator based on an integrated mutually coupled (IMC) distributed feedback (DFB) laser is demonstrated. The proposed MFC generator is simple and compact, only consisting of an IMC laser, a microwave signal generator, and a photodetector. By adjusting the bias currents of the three sections of the IMC laser and the modulation parameters, the bandwidth of the MFC can be significantly enhanced compared to the case adopting a solitary DFB laser. The characteristics of the MFC with the tuning current and the modulation parameters were investigated experimentally to determine the optimum operating condition. A broadband MFC with 40 GHz bandwidth within a ±5 dB amplitude variation was achieved under a modulation frequency of 2 GHz.