Abstract We demonstrated passively Q-switched 1-, 1.5-, and 2-μm fiber lasers by exploiting ferroferric-oxide nanoparticles (FONPs) as a broadband saturable absorber (SA). FONPs were prepared by a method of thermal decomposition, and then were mixed with sodium carboxymethylcelluose (NaCMC) to form a FONPs film. The FONPs film was sandwiched between two fiber ferrules to fabricate the FONPs SA, which had a broadband absorption from 800 to 2000 nm and nonlinear saturable absorption at 1-, 1.5-, and 2-μm. By inserting the same FONPs SA into the ytterbium, erbium and thulium doped fiber laser cavities, the stable passively Q-switching operation at 1039, 1560 and 1982 nm was realized for a threshold pump power of ∼82 mW, ∼62 mW and ∼830 mW, respectively. To the best of our knowledge, it is the first demonstration of the use of a single SA based on FONPs for wide-band Q-switching operation of fiber lasers from 1 to 2 μm.

中文翻译：

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用于调Q光纤激光器的宽带Fe3O4纳米颗粒可饱和吸收体

摘要 我们通过利用四氧化三铁纳米粒子 (FONP) 作为宽带可饱和吸收体 (SA) 展示了被动调 Q 1-、1.5- 和 2-μm 光纤激光器。FONPs 是通过热分解的方法制备的，然后与羧甲基纤维素钠 (NaCMC) 混合形成 FONPs 薄膜。FONPs 薄膜夹在两个光纤套圈之间以制造 FONPs SA，其具有 800 至 2000 nm 的宽带吸收和 1-、1.5-和 2-μm 的非线性可饱和吸收。通过将相同的 FONPs SA 插入掺镱、铒和铥光纤激光器腔，实现了在 1039、1560 和 1982 nm 的稳定被动调Q操作，阈值泵浦功率为~82 mW、~62 mW 和~830兆瓦，分别。据我们所知，