Tunable V-cavity laser based on half-wave multimode interference reflector in O-band

A tunable V-cavity laser based on half-wave multimode interference reflector (MIR-VCL) which operates in O-band is purposed and experimentally demonstrated. The superior side mode suppression ratio (SMSR) is achieved by the halfwave MIR, which is analyzed through the theory of multimode interference coupler. The laser is fabricated on the five quantum wells (QWs) InGaAlAs/InP wafer whose PL peak is about 1300 nm and has a compact device size of 500 mu m x 350 mu m. With the injection current on the gain electrode and short cavity electrode fixed, 27 channels with a spacing of about 100 GHz are obtained by tuning the injection current on the long cavity electrode. Experimental results show that among the whole tuning range, the SMSR ranges from 35 dB to 41.5 dB. By controlling the injection current on gain electrode and the TEC temperature, 51-channel wavelength tuning from 1288 nm to 1318 nm is obtained. The laser reaches its threshold when the total injection current is 65 mA. The tunable MIR-VCL in O-band has good potential for applications in 5G front-haul and datacenter networks.