Monolithic quantum-dot distributed feedback laser array on silicon

Electrically pumped lasers directly grown on silicon are key devices interfacing silicon microelectronics and photonics. We report here, for the first time, to the best of our knowledge, an electrically pumped, room-temperature, continuous-wave (CW) and single-mode distributed feedback laser array fabricated in InAs/GaAs quantum-dot gain material epitaxially grown on silicon. CW threshold currents as low as 12 mA and single-mode side mode suppression ratios as high as 50 dB have been achieved from individual devices in the array. The laser array, compatible with state-of-the-art coarse wavelength division multiplexing (CWDM) systems, has a well-aligned channel spacing of 20 0.2 nm and exhibits a record wavelength covering range of 100 nm, the full span of the O-band. These results indicate that, for the first time, to the best of our knowledge, the performance of lasers epitaxially grown on silicon is elevated to a point approaching real-world CWDM applications, demonstrating the great potential of this technology.