1.7μm全光纤锁模脉冲掺铥光纤激光器研究

Research on a 1.7 μm all-fiber mode-locked Tm-doped fiber laser

1.7μm超短脉冲光纤激光器在生物成像和材料加工等领域具有重要的应用前景,受到了科学家们的极大关注。基于非线性偏振旋转锁模技术,实验搭建了全光纤结构的1.7μm锁模脉冲掺铥光纤激光器。通过在激光器内加入光纤滤波器抑制掺铥光纤中的长波激光发射,同时采用纤芯泵浦的方式有效获得了1.7μm波段的增益。激光器输出脉冲的光谱中心波长为1 733 nm,3 dB带宽为6.3 nm。锁模脉冲的重复频率为19.56 MHz,平均功率为1.4 mW。同时,数值模拟了脉冲在激光器的腔内演化。文中提出的1.7μm全光纤锁模激光器有利于进一步提高1.7μm激光源的稳定性和集成度,在生物成像等领域具有重要的应用价值。

The 1.7 μm ultrashort pulse fiber laser has received great attention for its promising applications in various fields,such as bioimaging and materials processing.We experimentally built a 1.7 μm all-fiber structure mode-locked Tm-doped fiber laser based on the nonlinear polarization rotation technique.The optical gain at the 1.7 μm waveband is effectively obtained by using a core-pumping scheme,and the ASE at long wavelengths is suppressed by a fiber-based bandpass filter in the cavity.The proposed fiber laser delivers an ultrashort pulse with a central wavelength of 1 733 nm and a 3 dB bandwidth of 6.3 nm.The mode-locked pulse has a repetition frequency of 19.56 MHz and an average power of 1.4 mW.In addition,the evolution of the pulse inside the laser cavity is numerically simulated.The proposed 1.7 μm all-fiber mode-locked laser is beneficial to further improve the stability and integration of the 1.7 μm laser source,which could find important applications in fields such as bioimaging.