High-Power, Narrow-Linewidth, Miniaturized Silicon Photonic Tunable Laser With Accurate Frequency Control

We have demonstrated a hybrid-integrated silicon photonic (SiPh) tunable laser in a miniaturized package suitable for coherent modules in small form factors such as OSFP and QSFP-DD. Through the integration of an in-house-designed high-power semiconductor optical amplifier (SOA), the developed SiPh laser has achieved a record-high output power of 21.5 dBm across the C-band. Also, this laser exhibits narrow linewidths down to 60 kHz, SMSR larger than 50 dB, low relative intensity noise below -150 dB/Hz, and a broad tuning range of 65 nm. These performance parameters are preferable for 400 Gb/s and beyond coherent communications using advanced high-order modulation formats. Moreover, an on-chip integrated sensor technology was developed for accurate laser frequency control. We have achieved 1 GHz frequency stability of SiPh laser against SOA current changes or package temperature variations between 10 °C and 80 °C. We further show the feasibility of this developed SiPh laser for 64 Gbaud, 16/64 QAM coherent transmission by integrating with an in-house InP-PLC hybrid coherent optical subassembly (COSA).