提出了一种具有多波长可切换特性的掺铒光纤激光器,基于模场失配原理,利用无芯光纤结合保偏光纤构成一种光纤内马赫-曾德尔干涉仪(MZI)结构。通过调节MZI结构的曲率半径和偏振控制器,可得到稳定可切换的多波长掺铒光纤激光输出。输出多波长激光的最大波长间隔为40.184 nm,边模抑制比均大于50 dB。对输出激光的波长稳定性进行测试,在1 h内波长漂移量的最大值小于0.06 nm。研究结果表明,所提出的可切换多波长光纤激光器具有较大的输出波长范围和波长间隔、较高的边模抑制比及输出性能稳定等优点。

A switchable multi-wavelength erbium-doped fiber laser is proposed. Based on the mode field mismatch principle, an in-fiber Mach-Zehnder interferometer (MZI) is fabricated by the non-core fiber combing with the polarization maintaining fiber. A stable and switchable multi-wavelength fiber laser can be realized by adjusting the curvature radius of MZI and controlling the polarization controller. The maximum wavelength spacing of the output multi-wavelength fiber laser is about 40.184 nm, and the side mode suppression ratio is larger than 50 dB. In the test of output fiber laser stability, the maximum wavelength variation of output wavelength is less than 0.06 nm in 1 h. The research results show that the proposed switchable multi-wavelength fiber laser has the advantages of a wide switchable wavelength range and a wide wavelength spacing range, a high SMSR, a stable output, and so on.