Pulsed fiber lasers, with high peak power and narrow pulse widths, have been proven to be an important tool for a variety of fields of application. In this work, frontier and hot topics in pulsed fiber lasers were analyzed with 11,064 articles. Benefitting from the scientometric analysis capabilities of CiteSpace, the analysis found that passively mode-locked fiber lasers with saturable absorbers (SAs) based on two-dimensional (2D) materials have become a hot research topic in the field of pulsed fiber lasers due to the advantages of self-starting operation, high stability, and good compatibility. The excellent nonlinear optical properties exhibited by 2D materials at nanometer-scale thicknesses have become a particularly popular research topic; the research has paved the way for exploring its wider applications. We summarize the performance of several typical 2D materials in ultrafast fiber lasers, such as graphene, topological insulators (TIs), transition metal dichalcogenides (TMDs), and black phosphorus (BP). Meanwhile, we review and analyze the direction of the development of 2D SAs for ultrafast fiber lasers.

Two-dimensional (2D) arsenic–phosphorus (AsP), as a derivative of black phosphorus (BP), has achieved great progress in regards to preparation methods, property modulation, and front application, which can be attributed to the following two points. The first is that a method has been developed of alloying BP with the congener element arsenic to produce high-quality AsP; the second is that stable AsP possesses unique electronic and optical properties. To conclude the continuous and extensive research, this review focuses on synthesis details, modulation strategies, and application advances of stable AsP. Firstly, several pathways to prepare AsP with different phases are listed. Secondly, multiple solutions to optimize the electronic properties of AsP are discussed, such as strain regulation and composition tuning, and especially composition tuning of AsP including element modification, atomic substitution, and dopant participation, which can bring about adjustments of the lattice structure, bandgaps, and electronic properties. Based on the regulated AsP, applications in infrared photodetectors, high-performance transistors, and efficient-energy storage devices and so on have been widely developed. Although there are challenges ahead, this review may bring new insights into and inspirations for further development of 2D AsP-based materials and devices.