简要阐述2 μm激光光源的广泛应用需求,分析掺铥铝酸钇(Tm:YAP)晶体的能级结构和吸收光谱特性,报道了采用激光二极管(LD)端面抽运Tm:YAP晶体的方式,实现室温下2 μm激光的高效输出。在激光二极管输出功率为19 W时, 2 μm连续激光输出功率为6.5 W,光光转换效率达34％,斜率效率为47.5％。经过声光(AO)Q开关进行调制后,在重复频率10 kHz下,获得5.4 W的动态激光输出,激光单脉冲宽度为70 ns,激光二极管输出功率到2 μm激光动态输出功率的转换效率为28％,斜率效率为42％。通过实验验证了激光二极管端面抽运Tm:YAP晶体在室温下高效输出的特性。

The application of 2 μm laser source is introduced, and the energy level diagram and absorption spectrum of Tm:YAP crystal are analyzed. A laser diode end-pumped Tm:YAP laser is reported. A high efficient 2 μm laser is attained at room temperature. The CW output power is 6.5 W with the laser diode output power of 19 W, the optical-to-optical efficiency is up to 34% and the slope efficiency is 47.5%. While acoustic-optical (AO) Q-switch is working at modulation mode, the output power of 2 μm at the repetition of 10 kHz is 5.4 W, single pulse width is 70 ns, optical-to-optical efficiency is 28% and the slope efficiency is tested to be 42%.