低损耗微腔作为芯片级光与物质相互作用的平台，以其小体积、低能耗、易集成的优势在孤子光学频率梳（简称“孤子光梳”）领域得到广泛关注，成为片上飞秒光源的理想选择之一。当前，微腔孤子梳已在多种材料平台上得到实现，并以其宽谱、高相干的飞秒脉冲特性，在精密测距、激光雷达、时频计量、相干通信等领域得到广泛应用。但是，当前微腔孤子梳领域依然存在以下挑战。在理论方面，为了在低损耗微腔中实现孤子光梳，通常需要腔内的色散与非线性、增益与损耗达到平衡，在该过程中，当前研究尚未深入探索高阶色散、热光转换效应的影响。在工艺方面，常规氮化硅微腔加工工艺存在化学计量比、应力与厚度难以平衡的挑战，从而造成了厚氮化硅膜的皲裂和氮化硅微腔的低Q值。在孤子频梳产生方面，微腔克尔孤子难以泵浦锁定。在微腔非线性光学研究方面，当前研究尚未探索氮化硅微腔中的二阶非线性效应。 本论文首先介绍了微腔克尔光梳的起源与应用，阐明了微腔克尔光梳的重要意义（第1章）。以麦克斯韦方程组为基础，提出了协同色散设计的概念，并对氮化硅光梳的结构进行了优化设计，再引入非线性效应，在原有Lugiato-Lefever Equation的基础上探讨了高阶色散、热光转换效应的影响，推进了集成光梳理论的发展（第2章）。在该理论的指导下，通过对不同材料体系中非线性系数与微腔损耗的比较，确定了以氮化硅为核心的CMOS兼容加工工艺，并提出载气辅助的氮化硅薄膜生长工艺，解决了当前氮化硅薄膜生长中最难以平衡的化学计量比、应力与厚度问题；提出了缓冲层与保护层的概念，有效地解决了厚氮化硅膜的皲裂问题，从而实现了百万Q值且反常色散的氮化硅微腔的加工（第3章）。基于氮化硅微腔，研究了微腔内的非线性光与物质相互作用过程。在三阶非线性效应的研究中，针对由微腔双稳态曲线所导致的孤子难锁定挑战，以前述的光热耦合理论为指导，提出了激光器功率扫描方法，实现了微腔孤子光梳的泵浦与锁定，降低了泵浦系统的复杂度（第4章）。在二阶非线性的研究中，利用全光极化效应，打破了氮化硅的中心对称性，在不存在内秉偶阶非线性效应的氮化硅微腔中产生了二阶非线性效应，并结合高阶色散效应，首次在氮化硅微腔中实现了近红外泵浦的宽谱可调谐可见激光出射（第5章）。 综上，本论文实现了我国自主设计研发、工艺制备、测试封装的氮化硅微腔孤子光梳，并在钱学森空间技术实验室等单位得到了应用，推动了我国集成光电子领域的发展与进步。

Owing to its compact size, low power consumption, and ease of integration, low-loss microcavity, as an on-chip platform for light-matter interaction, attracted much attention from the field of soliton optical frequency comb. Hence, microcavity soliton optical frequency comb (microcomb) became one of the ideal candidates of integrated femtosecond laser source. So far, microcomb has been realized based on many material platforms, leading to broad applications in precise ranging, LIDAR, spectroscopy, time-frequency metrology, coherent communication, microwave photonics, frequency synthesis, and quantum computing. However, conventional microcombs still face following challenges. In theory, to achieve soliton in microcavity, we usually need to balance the dispersion and nonlinearity as well as gain and loss. In this process, high-order dispersion and thermal-optical effect have not been fully explored yet. In fabrication, it is still challenging to balance the stress, thickness, and stoichiometric in conventional silicon nitride microcavity fabrication process, leading to the crack of thick silicon nitride film and low-quality factor of silicon nitride microcavity. In the generation of microcomb, it is difficult to pump and lock the microcavity Kerr solitons. In the study of microcavity nonlinear optical process, the second order nonlinear process has not been explored yet. This thesis first introduced the history and applications of microcomb with its implication discussed (Chapter 1). Then, we introduced the concept of cooperative dispersion design based on Maxwell's equations. According to this concept, we optimized the structures of silicon nitride microcombs. Then the Lugiato-Lefever equation (LLE), which describes the nonlinear interaction between light and microcavity, was derived with the effects of photothermal coupling and high order dispersion considered, developing the theoretical study of integrated optical combs (Chapter 2). Under this theoretical guidance, CMOS-compatible silicon nitride is employed as the major platform for microcavity fabrication in the consideration of the process compatibility, integration compatibility, nonlinear coefficient, and microcavity loss. To balance the stress, thickness, and stoichiometric ratio, we proposed and demonstrated the carrier gas-assisted growth process. To effectively resolve the crack of thick silicon nitride film, we introduced the buffer and protective layers, effectively resolving the crack of thick silicon nitride film and in turn realizing the fabrication of silicon nitride-based microcavity with Q factor over a million as well as anomaly dispersion (Chapter 3). Based on silicon nitride microcavity, we studied the nonlinear light-matter interaction in microcavity. In the study of the third-order nonlinear effects, the existence of microcavity bistable curve makes it difficult to pump and lock the microcavity Kerr solitons. Guided by the proposed photothermal coupling theory, we proposed and demonstrated a laser power scanning method to realize the pumping and locking of the microcavity solitons optical comb, dramatically simplifying the pumping system (Chapter 4). In the study of second-order nonlinear effects, we leveraged the all-optical polarization effect to break the central symmetry of the silicon nitride and in turn generate second-order nonlinear effects in the silicon nitride microcavity without even-order nonlinear effects. Combined with the high-order dispersion effect, the near-infrared pumped wide-spectrum tunable visible laser output is achieved for the first time in the silicon nitride microcavity (Chapter 5). In summary, this dissertation realized micro-combs’ full development process including designing, film depositing, etching, soliton generating and device packaging in China, leading to the applications in many institutes such as Qian Xuesen Space Technology Laboratory. This work promotes the development of integrated optoelectronics of China.