Electronically Tunable Distributed Feedback (DFB) Laser on Silicon

An electronically tunable distributed feedback (DFB) laser heterogeneously integrated on a silicon photonics platform is experimentally demonstrated. Tuning is achieved through carrier injection into the tuning layer of a tunable twin-guide III-V membrane on silicon. A 2 nm continuous tuning range is achieved with a single tuning current. Continuous-wave single-mode laser operation with a side-mode suppression ratio larger than 44 dB across the tuning range is obtained. Measured wavelength switching times are on the order of 3 ns and non-return-to-zero on-off keying direct modulation at 12.5 Gbit s(-1) is readily achieved. This work can be a major advance toward the realization of optical burst or packet switching systems for future data center networks.