【摘要】 高相干、宽调谐硅基集成片上光源是支撑下一代大容量相干光通信、高精度激光雷达及片上精密计量系统的核心。系统综述了硅基集成外腔激光器的精准相频调控技术及其最新研究进展。首先，阐述了通过Ⅲ-Ⅴ族增益介质与低损耗硅基无源外腔集成实现单纵模运转、线宽压窄与波长调控的物理机制。随后，重点讨论了波长精准定标与锁定、激光稳频以及针对调频连续波（FMCW）应用的线性扫频技术。进一步综述了近年来在线宽压窄、波长调谐与锁定、功率放大以及集成化激光稳频方面的标志性成果，并探讨了硅基外腔激光器在相干通信、激光雷达、光纤传感领域的应用潜力。最后，针对当前集成度、长期稳定性和系统级应用拓展的挑战，探讨了未来异质集成、光电融合与智能化调控的发展方向。更多还原

【Abstract】 Significance High-coherence and widely tunable laser sources are key enabling components in modern silicon photonic systems,playing a critical role in coherent optical communications,frequency-modulated continuous-wave （FMCW） Li DAR,precision metrology,and distributed fiber-optic sensing.With the rapid growth of data traffic,increasing demands on sensing accuracy,and the continuous evolution toward system-level integration,laser sources are no longer required to merely provide stable emission,but must instead support precise phase and frequency control with high stability,wide tuning range,and low noise.Different applications impose distinct and often competing performance requirements on laser sources.In coherent communication systems,narrow linewidth and low phase noise directly determine achievable modulation formats,transmission capacity,and bit error rate,while precise wavelength locking to standardized channels is essential for dense wavelength division multiplexing.In Li DAR and three-dimensional imaging,high output power and broadband linear frequency sweeping are required to enhance detection range and spatial resolution.In fiber-optic sensing and precision metrology,long-term frequency stability and low drift are critical for achieving high sensitivity and measurement accuracy.Conventional semiconductor lasers are fundamentally limited by short cavity length and intrinsic noise mechanisms,which restrict their linewidth and frequency stability.Although discrete external-cavity lasers can achieve excellent coherence and tunability,they are not compatible with large-scale integration.Silicon-based integrated external-cavity lasers,realized through integration of III-V gain media with low-loss silicon photonic circuits,have therefore emerged as a promising solution,offering both high performance and scalability.This review focuses on precise phase-frequency control technologies for silicon-based integrated external-cavity lasers and their applications.Progress This paper systematically reviews the working principles,key phase-frequency control techniques,recent research advances,and representative applications of silicon-based integrated external-cavity lasers.We first introduce the fundamental configurations and physical mechanisms of two mainstream device architectures （Figs.1??3）.Subsequently,three core phase-frequency control techniques are discussed in detail.For wavelength tuning and locking,implementations based on Fabry-Pérot （FP） etalons combined with servo feedback circuits are introduced （Fig.4）,enabling precise alignment with International Telecommunication Union （ITU） channels.For frequency stabilization,the widely adopted PoundDrever-Hall （PDH） technique is described （Fig.5）,which locks the laser to a high-stability optical reference to enhance long-term stability.For linear frequency sweeping in FMCW applications,two representative linearization approaches,namely iterative predistortion and electro-optic phase-locked loops,are comparatively analyzed （Fig.6）,both of which effectively suppress chirp nonlinearity.Furthermore,recent representative research progress is comprehensively summarized.Advances in narrow-linewidth tunable lasers are reviewed,including linewidth reduction to the Hz level enabled by low-loss extended cavities and high-Q resonators（Fig.7）,wide-range mode-hop-free tuning and high-linearity frequency sweeping （Fig.8）,as well as power scaling strategies （Fig.9）.A comparative analysis of material platforms,including Si,Si₃N₄,and lithium niobate on insulator （LNOI）,is also provided.In addition,wavelength-locking technologies based on discrete FP etalons （Fig.10） and integrated wavelength-locked lasers （Fig.11） are discussed.Progress in integrated frequency stabilization is reviewed,covering miniaturized optical frequency references （Fig.12）,onchip reference cavities （Fig.13）,and dual-polarization self-referenced stabilization schemes （Fig.14）.Finally,the application potential of silicon-based external-cavity lasers is validated through system-level demonstrations in space coherent optical communication （Figs.15??17）,FMCW Li DAR （Fig.18）,and distributed fiber-optic sensing （Figs.19??23）.Conclusions and Prospects Silicon-based integrated external-cavity lasers have achieved significant progress in linewidth reduction,wavelength tuning,frequency stabilization,and power scaling,demonstrating strong potential for next-generation coherent photonic systems.By leveraging the integration ofⅢ-Ⅴgain media with low-loss photonic circuits,these devices effectively combine their respective advantages,enabling high-performance and scalable on-chip laser sources.Despite these advances,several challenges remain for practical deployment.A key limitation is the lack of high-stability on-chip optical frequency references,which constrains long-term absolute frequency stability.Future efforts should focus on complementary metal oxide semiconductor （CMOS） compatible materials with improved thermal stability and hybrid stabilization schemes combining self-injection locking with integrated absorption-based references.In parallel,advances in multi-material integration and optoelectronic co-design,enabled by wafer-scale bonding and advanced integration technologies,will be essential for achieving compact,lowpower,and system-level solutions.Furthermore,intelligent control strategies such as machine-learning-assisted optimization are expected to enhance real-time phase and frequency stabilization in complex environments.Overall,these developments will drive highly integrated,high-performance laser sources for applications in communication,sensing,and precision metrology.更多还原