硅光子芯片外腔窄线宽半导体激光器

Narrow linewidth external cavity semiconductor laser based on silicon photonic chip

随着超高速光互连、相干光通信、相干检测等技术的不断发展,对激光光源的线宽、相频噪声、可调谐性和稳定性等都提出了更为严格的要求。利用基于CMOS(Complementary Metal Oxide Semiconductor)工艺的硅光子芯片与半导体增益芯片各自的优势,将二者准单片集成实现结构紧凑、低功耗和高稳定性的窄线宽半导体激光器成为近年的研究热点。该结构可通过微环谐振器、环形反射镜和马赫曾德干涉仪等提供光反馈压窄线宽,并实现宽调谐范围和稳定功率输出。本文主要阐述了硅光子芯片外腔半导体激光器的最新研究进展,针对几种包含微环谐振器的结构进行了分类介绍,深入讨论了增加耦合效率和降低端面反射率等技术难题。针对未来空间光通信和光互连等应用前景,展望了该类激光器在功率提升和光子集成方面的未来发展方向。

With the development of ultra-high speed optical interconnection,coherent optical communication and coherent detection technology,more stringent requirements are put forward for the linewidth,power and stability of laser source.Based on their own different advantages of silicon photonic chip using CMOS(Comple-mentary Metal Oxide Semiconductor)technology and semiconductor gain chip,the narrow linewidth semiconductor laser with compact structure,low power consumption and high stability can be realized by one single silicon photonic chip and one single semiconductor gain chip integrations,which becomes a hotspot in recent years.The structure can provide the optical feedback to narrow the linewidth by microring resonator,loop mirror and Mach-Zehnder interferometer,and realize the wide tuning range and stable output power.In this paper,the latest research progress of silicon photonic chip external cavity semiconductor laser and several structures containing microring resonators are introduced,and the technical problems,such as increasing the coupling efficiency and reducing the reflectivity of the end face,are discussed in detail.For future applications of space optical communication and optical interconnection,we prospect the future research direction of such lasers in power upgrading and photonic integration.