高功率650~660 nm波段激光器在可见光光电对抗领域具有重要作用，目前该波段光源由固体激光器通过半导体激光器泵浦并倍频输出，输出功率高、光束质量近衍射极限，但转换效率低。半导体激光器的转换效率高，但输出功率低，需要通过增加激光单元的方法提升功率，并通过激光合束的方式提升光束质量。文中提出外腔光谱合束的650 nm波段半导体激光器结构，通过实验验证可实现连续功率为7.3 W、光谱线宽为6.45 nm、电光转换效率为23.4%的650 nm波段激光输出，光束质量为M²_X=1.95，M²_Y=11.11，接近固体激光器，未来通过增加合束的激光单元数量并结合偏振合束可以获得更高功率的650 nm波段激光。

This work demonstrates the generation of short pulse duration and high-beam-quality laser pulses using transient stimulated Brillouin scattering at a high repetition rate. Thermal effects and optical breakdown are identified as the main factors that restrict energy reflectivity and beam quality under high repetition rates and transient situations. Through experimental analysis, the interaction length and focal point size are determined to be the key parameters in reducing the thermal effect by reducing the absorption of the laser pulse by the medium. The obtained results show that pulses with a duration of 175 ps and beam quality M² of around 1.2 can be achieved with a maximum energy reflectivity of over 40% under an interaction length of 50 mm. Furthermore, at an interaction length of 90 mm, a pulse output with a minimum duration of 115 ps (0.5τ_Q) is achieved.

通过小角度V形腔外腔光谱合束将两个808 nm半导体激光器合束，提高半导体激光器的输出功率及光束质量。两个合束单元分别工作在795.8 nm和800.5 nm，将所获光束通过非线性光学方法进行频率转换。外腔光谱合束实现输出功率为6.5 W快慢轴光束质量M²=2.2×18.5的光束输出，所获光束慢轴M²因子相较于自由运转单管激光器提高了30%，外腔光谱合束效率为83%。基于所获光源，实现了半导体激光器小角度V形腔外腔光谱合束和频，获得输出功率为18.3 mW波长为401.0 nm的蓝光输出，和频效率为0.28%。

高功率、高重复频率纳秒脉冲激光广泛应用于激光切割、激光焊接等领域。随着激光重复频率的提升，特别是高于50 kHz时，单个周期有限的时间内难以积累足够的上能级粒子，调Q脉冲的稳定性成为了激光器设计的难点。当前主要采用主振荡器的功率放大器（MOPA）方案，直接振荡获得兼具高功率、高重复频率及高光束质量的纳秒脉冲激光还比较困难。通过对激光动力学过程的仿真模拟，定量分析了高重复频率调Q过程中脉冲强度稳定性与泵浦速率的关系，并利用负透镜使振荡器工作在具有较大基模体积的热近非稳区，实现了Nd:YAG声光调Q激光振荡器在高重复频率、高功率、高光束质量三方面的均衡设计。首次利用侧泵模块实现了100 kHz高功率高光束质量纳秒脉冲激光的直接振荡产生，脉冲强度的离散系数仅为0.041，激光输出功率超过142 W，脉冲宽度为165 ns，光束质量因子M²为1.5。

报道了采用纳秒脉冲激光器泵浦基于掺杂氧化镁周期极化铌酸锂(MgO:PPLN)晶体的高光束质量、闲频光谐振中红外光参量振荡器。通过选取曲率半径为200 mm的凹面输入镜和平面输出镜来建立平凹腔，实现了高光束质量的近-中红外激光输出。当输入的最大泵浦能量为21 mJ时，输出信号光和闲频光的最大能量分别为3.2 mJ和1.12 mJ，对应信号光和闲频光的斜效率分别为24%和9%。通过在25~200 ℃范围内改变MgO:PPLN晶体温度，实现信号光波长1.505~1.566 μm和闲频光波长3.318~3.628 μm的激光调谐输出。由于闲频光单谐振的光参量振荡器具有较大的衍射损耗和光束发散角，可以提高输出闲频光的光束质量。采用刀口法测量得到中红外激光在两个正交方向的光束质量因子分别为 $ {M}_{x}^{2}\approx 1.2 $和 $ {M}_{y}^{2}\approx 1.2 $。

A 1.5 J Nd:LuAG ceramic active mirror laser amplifier with a high beam quality is demonstrated in which a 0.8% (atomic fraction) Nd-doped Nd:LuAG ceramic disk with a diameter of 64 mm and a thickness of 5.5 mm is used as a laser gain medium. A maximum single-pass small-signal gain of 2.59 is measured when the pump energy is 11.5 J, with an injected seed energy of 0.4 J; a maximum output energy of 1.5 J is obtained at the repetition rate of 10 Hz. A far-field beam spot 1.25 times the diffraction limit (DL) is achieved by using a stimulated Brillouin scattering phase conjugation mirror (SBS-PCM) for wavefront correction.