Zhao Hanru, Feng Meixin, Liu Jianxun, Sun Xiujian, Tao Tao, Sun Qian, Yang Hui
School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China.
Key Laboratory of Nano-Devices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences (CAS), Suzhou 215123, China.
Nanophotonics. 2023 Jan 3;12(1):111-118. doi: 10.1515/nanoph-2022-0577. eCollection 2023 Jan.
GaN-based microring lasers grown on Si are promising candidates for compact and efficient light sources in Si-based optoelectronic integration and optical interconnect due to their small footprints, low mode volume, low power consumption, and high modulation rate. However, the high symmetry of circular microcavity leads to isotropic emission, which not only reduces the light collection efficiency, but also affects other adjacent devices during data transmission. In this study, the unidirectional lasing emission of room-temperature current-injected GaN-based microring laser was realized by coating metal Ag on the microring sidewall and integrating a direct coupled waveguide. The light was efficaciously confined in the cavity and only emitted from the waveguide, which avoided optical signal crosstalk with other adjacent devices. Furthermore, we integrated a microdisk at the other end of the waveguide as a photodetector, which could effectively detect the output power of the microring laser from the direct coupled waveguide. Therefore, a preliminary on-chip integration of GaN-based microring laser, waveguide and photodetector on Si substrate was successfully demonstrated for the first time, opening up a new way for on-chip integration and optical interconnect on a GaN-on-Si platform.
生长在硅上的氮化镓基微环激光器由于其占地面积小、模式体积小、功耗低和调制速率高，是硅基光电集成和光互连中紧凑型高效光源的有前途的候选者。然而，圆形微腔的高对称性导致各向同性发射，这不仅降低了光收集效率，而且在数据传输过程中还会影响其他相邻器件。在本研究中，通过在微环侧壁上涂覆金属银并集成直接耦合波导，实现了室温电流注入氮化镓基微环激光器的单向激光发射。光被有效地限制在腔内，并且仅从波导发射，这避免了与其他相邻器件的光信号串扰。此外，我们在波导的另一端集成了一个微盘作为光电探测器，它可以有效地检测来自直接耦合波导的微环激光器的输出功率。因此，首次成功地在硅衬底上初步演示了基于氮化镓的微环激光器、波导和光电探测器的片上集成，为基于硅上氮化镓平台的片上集成和光互连开辟了一条新途径。
