I am Yifan Sun. I study nonlinear dynamics in optics.
Email: ivansuun@gmail.com; yifan.sun@ulb.be
My research focuses on nonlinear photonics, with particular emphasis on optical solitons, cavity dynamics, and multimode nonlinear systems. I work at the intersection of nonlinear optics, applied mathematics, and photonic device physics, developing theoretical and numerical frameworks to understand how localized structures emerge, evolve, and remain stable in driven-dissipative optical systems. A central theme of my work is to reveal how complexity in modern photonic platforms—such as multimode coupling, hybrid nonlinearities, and noise—can be transformed from a limitation into a resource for controlling light.
Over the course of my career, I have worked on a broad range of nonlinear optical systems, from mode-locked nanolasers and multimode fiber solitons to cavity solitons in Kerr resonators. My earlier work explored ultrafast nonlinear dynamics in semiconductor nanolasers, where I showed how mode locking can arise in compact photonic crystal cavities. I later expanded into multimode fiber physics, investigating spatiotemporal solitons, multimode interactions, and high-dimensional nonlinear wave dynamics. More recently, my research has focused on driven optical cavities, where I study dissipative solitons, breathers, and related localized states in both Kerr and parametrically driven systems.
My current research aims to build predictive design tools for next-generation multimode and hybrid photonic resonators. In particular, I am interested in multimode Kerr cavities and hybrid χ(2)/χ(3) systems, where multiple fields, modes, or frequencies interact in a nonlinear resonator. These systems open new possibilities for frequency-comb generation, multicolor synchronization, and parametrically driven cavity solitons, but they also introduce new instability mechanisms and noise pathways. By combining reduced-order modeling, bifurcation analysis, large-scale simulations, and noise theory, I seek to establish stability maps and design rules that can directly guide experiments.
More broadly, my goal is to contribute to a predictive theory of complex photonic architectures that links fundamental nonlinear dynamics with experimentally relevant observables such as coherence, timing jitter, phase noise, and conversion efficiency. I work closely with experimental collaborators to create a strong theory-experiment feedback loop, where models do not simply explain observations after the fact, but actively help identify robust operating regimes and new physical phenomena. Through this approach, I hope to advance both the fundamental understanding of dissipative nonlinear systems and the development of practical photonic technologies for precision measurement, frequency combs, and optical signal control.