Widely tunable dual-mode amplified feedback laser with mode separation covering 60-GHZ band

A monolithic integrated amplified feedback laser (AFL) is experimentally demonstrated as a new solution to generate dual-mode lasing with beating-frequency around 60 GHz. This laser consists of a complex-coupled distributed feedback laser (DFB) and an integrated feedback cavity, which is formed by a phase section and an amplifier section. Stable dual-mode emission, with high side modes suppression ratio (SMSR) is achieved under proper bias condition. By tuning the injection currents of the phase and amplifier section, the beating-frequency can be continuously tunable in the range of 46.8 to 72 GHz. Benefit from the compactness and wide tuning range, the device will be a potential candidate for hybrid fiber-wireless access network and high frequency optical microwave generation.