Topological photonics has emerged as a powerful platform to explore topological physics and design photonic devices that remain robust in the presence of disorder. Early advances centered on photonic crystals and coupled microresonator arrays, but these studies were largely confined to the linear regime. In parallel, microresonator frequency comb technology has advanced dramatically over the past decade, enabling strong on-chip optical nonlinearities and compact frequency comb generation. By uniting these two frontiers, we have realized a new class of topological frequency combs (Science, 2024), demonstrated topological mode locking (Science Advances, 2025), and introduced nested frequency-phase matching for general nonlinear optics (Science, 2025). This emerging platform opens new avenues for both topological photonics and nonlinear optics, including quantum metamorphosis and infinitely nested solitons, as well as multi-dimensional dispersion engineering with turnkey mode locking (in preparation, 2025). Looking ahead, we envision on-chip topological squeezing and systematic optimization of device architectures as the next milestones.

Pizza and drinks will be served after the seminar in ATL 2117.