A passively Q-switched multi-wavelength erbium-doped fiber laser modulated by 12° tilted fiber Bragg grating

• Published in: Infrared physics & technology Vol. 133; p. 104806
• Main Authors: Zhang, Meixia, Jiang, Xiwen, Xu, Yan, Cui, Chenghao, Hong, Zhifeng, Zhang, Ran, Liu, Xiaojuan, Yan, Peiguang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2023
• Subjects: 12°tilted fiber Bragg grating (12°TFBG); Erbium-doped fiber laser (EDFL); Multi-wavelength fiber lasers; Q-switched; Q-switched; 12°tilted fiber Bragg grating (12°TFBG); Multi-wavelength fiber lasers; Erbium-doped fiber laser (EDFL)
• ISSN: 1350-4495; 1879-0275
• DOI: 10.1016/j.infrared.2023.104806

•A 12° TFBG is prepared by femtosecond laser direct inscription method. And a pulse multi-wavelength erbium-doped fiber laser (EDFL) passively Q-switched by the as-prepared 12° TFBG is exclusively and systematically demonstrated for the first time. The discussed result is interesting and may add new knowledge within the field of research.•The transmission spectrum of 12° TFBG and the polarization dependent loss (PDL) declare that the 12° TFBG can serve as both a filter and a polarizer. So, in the paper, it’s not only systematically verified that the 12° TFBG is capable of acting an ideal modulator for ultrafast pulse generation, but also the multi-wavelength Q-switched operation obtained in this work benefits from the filtering effect and polarization dependent loss (PDL) effect of the 12° TFBG.•The experimental results are comparable to other Q-switched multi-wavelength EDFLs reported so far, and during the experiment, the 12° TFBG exhibits excellent stability and reliability.•The work not only provides a reliable reference about the equivalent SA performance of 12° TFBG, but also enriches the studies of passively Q-switched lasers based on different kinds of modulators. Sufficient attention from researchers should be focused on relative studies, which may open up a new research field in the nearest future. As a promising small-angle TFBG, the 12° tilted fiber Bragg grating (TFBG) has been successfully used in biochemical sensors, fiber optic anemometers, and continuously tunable photon fraction time differentiators. On the other hand, multi-wavelength Q-switched fiber lasers have widely potential and practical applications in various fields, such as laser processing, laser marking, medical diagnosis, military applications, and so on. In this paper, first, a 12° TFBG is prepared by femtosecond laser direct inscription method (FSL-DIM), then, a pulse multi-wavelength erbium-doped fiber laser (EDFL) passively Q-switched by the as-prepared 12° TFBG is exclusively and systematically demonstrated for the first time. When the pump power is raised from 100 mW to 500 mW, the repetition rate is boosted from 51.64 kHz to 149.4 kHz resulting in a repetition rate range about 97.76 kHz, while the pulse duration is compressed from 3.928 μs to 1.033 μs. The average output power monotonically increases up to the maximum value of 6.357 mW corresponding to the maximum pulse energy of 42.55 nJ. The signal-to-noise ratio (SNR) is measured to be 53 dB, which indicates a high stability. The experimental results are comparable to other Q-switched multi-wavelength EDFLs reported so far, and during the experiment, the 12° TFBG exhibits excellent stability and reliability. As far as we can explain, the multi-wavelength Q-switched operation obtained in this paper benefits from the filtering effect and polarization dependent loss (PDL) effect of the 12° TFBG. The work not only provides a reliable reference about the effective-SA performance of 12° TFBG, but also enriches the studies of passively Q-switched lasers based on different kinds of modulators.