锥形光纤能够有效兼顾非线性效应抑制和模式控制，具备实现高功率、高光束质量光纤激光的潜力。近期国防科技大学研制了锥形掺镱光纤，采用1018 nm光纤激光后向级联泵浦实现了20.2 kW 激光输出，光束质量β因子平均值优于2，拉曼抑制比为33 dB。研究结果展示了锥形光纤在实现万瓦级高光束质量激光方面的优势。

与常规的自发拉曼散射相比，受激拉曼散射 (SRS) 经常使用两束光场 (泵浦光和Stokes光)，这为偏振操控SRS过程提供了一个额外的自由度。为此，开展了泵浦光分别为圆偏振和线偏振的SRS对比研究。首先，基于非线性耦合波方程，从理论上分别推导了泵浦光为圆偏振和线偏振时 (Stokes光始终保持线偏振) SRS信号强度表达式。随后，以具有球对称的甲烷分子为例，实验测量了上述两种偏振光泵浦下甲烷分子υ₁和υ₃振动模在2800~3100 cm^-1的SRS光谱。实验结果与理论分析一致表明：SRS的信号强度不仅与泵浦光的偏振态有关，还与待测分子振动模式的对称性紧密相关。本研究结果为SRS的偏振应用提供了有益启示。

We demonstrate the generation of a unique regime of multiple solitons in a Tm-doped ultrafast fiber laser at ∼1938.72 nm. The temporal pulse-to-pulse separation among the multiple solitons, 10 in a single-pulse bunch, increases from 0.89 ns to 1.85 ns per round trip. In addition, with the increasing pump power, the number of bunched solitons increases from 3 up to 24 linearly, while the average time separation in the soliton bunch varies irregularly between ∼0.80 and ∼1.52 ns. These results contribute to a more profound comprehension of nonlinear pulse dynamics in ultrafast fiber lasers.

We present a study on a watt-level acousto-optically Q-switched Pr:YLF laser at three different repetition rates (10 kHz, 20 kHz, and 50 kHz) for the first time, to the best of our knowledge. The corresponding average output powers and pulse widths were measured to be 1.14 W, 1.2 W, and 1.32 W, and 40 ns, 52 ns, and 80 ns, respectively. A maximum pulse energy of 0.11 mJ was obtained, corresponding to a peak power of up to 2.8 kW at a repetition rate of 10 kHz. The simulated dynamics of a fast Q-switched Pr:YLF laser is in agreement with the experiment. The laser’s ability to generate stable pulses with high peak power and short pulse width makes it highly desirable for various practical applications, such as laser machining and material processing.