Generation of Supertoroidal Pulses with Controlled Topologies

Abstract Toroidal electromagnetic excitations have been recognized as the third fundamental excitations besides classic electric and magnetic dipoles, offering great promise for next-generation information carriers. However, a big step ahead blocking the practical implementation remains the deterministic generation and control of the full family from toroidal to supertoroidal pulses with tailored topological orders. Here, we experimentally demonstrate supertoroidal pulse generation by both passive and active spatiotemporal metasurfaces. We also observe and manipulate their nontrivial properties—including fractal-like singularities, deep-subwavelength skyrmions, nondiffracting propagation, and space–time superoscillations—which were previously predicted but unrealized. These findings complete a missing chapter of supertoroidal electrodynamics and open immediate horizons for ultra-capacity robust communications and exotic light-matter interactions.