Optical Solitons Dominated by Pure‐High‐Even‐Order Dispersion: Research Progress of Pure‐Quartic Solitons

ABSTRACT Pure‐quartic solitons (PQSs) are a special type of optical solitons that exist stably depending on the balance between negative fourth‐order dispersion and self‐phase modulation (SPM). Their evolution mechanism is different from the balance between group‐velocity dispersion and nonlinear effects on which traditional solitons rely. Recent experimental and theoretical studies have demonstrated that the balance between pure‐quartic dispersion and SPM enables the formation of stable pure‐ higher‐order dispersion solitons. Here, we systematically summarize the experimental implementations and numerical simulation studies of PQSs in diverse cavity configurations, which used different approaches for constructing a pure‐quartic dispersion regime. PQSs' special energy‐width scaling characteristics and temporal oscillating tail structure may bring new applications to the field of ultrafast lasers. This will not only advance the development of ultrafast lasers, but also lay a solid foundation for breakthroughs in other fields, including on‐chip frequency combs, supercontinuum generation, and advanced modulation formats for communications.