Microresonators based frequency combs, microcombs, have attracted huge interest in the last decades for their revolutionary performance of compact size, flexible comb spacing, and broad bandwidth.

Over the past decades, researchers have demonstrated conventional solitons, stretched pulses, self-similar pulses, and dissipative solitons by managing the dispersion and nonlinearity of fiber lasers.

Hypergap materials reveal a second transparent region above the bandgap, overturning assumptions about optical limits and enabling low-loss light control, wavelength conversion, and new photonic ...