Generation of stable nanosecond dual-pulse in an erbium-doped fiber laser with normal dispersion. (1st November 2017)

• Record Type: Journal Article
• Authors: Li, Kexuan; Song, Yanrong; Tian, Jinrong; Guoyu, Heyang; Xu, Runqin
• Is Part Of: Optics & laser technology. Volume 96(2017)
• Page Start: 18
• Page End: 22
• Publication Date: 2017-11-01
• Subjects: Fiber lasers -- Mode-locked lasers -- Nanosecond square pulse -- Dual-pulse; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2017.04.028
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: A stable nanosecond dual-pulse is generated in an erbium-doped fiber laser. The duration of the first pulse can be continuously tuned by simply changing the pump power. By properly selecting the parameters of the laser cavity, such dual-pulse can be obtained. Such a nanosecond dual-pulse laser has potential applications in micromachining. Abstract: Because of the special needs for nanosecond double pulse applications in micromachining and material processing, we demonstrated a stable nanosecond dual-pulse erbium-doped fiber laser based on nonlinear polarization rotation technology. The fiber laser operates in a normal dispersion regime with a length of 256 m OFS-980 fiber. With the pump power of 1120 mW, the laser generates a highly stable dual-pulse train with the pulse widths of 6.2 ns and 1.2 ns respectively. By simply changing the pump power, the pulse width of one of dual-pulse can be tuned from 2.1 to 6.2 ns while the other pulse keeping almost the same duration of 1.2 ns. The maximum dual-pulse energy is about 72.5 nJ with a repetition rate of 783.3 kHz. The formation of such nanosecond dual-pulse is attributed to the pulse splitting and depends on the parameters of the laser cavity, such as the cavity-length and the state of polarization controller. The experiment of a single square pulse splitting into different shapes of nanosecond dual-pulse was demonstrated.