复合型金属网栅耦合输出镜是大功率光泵THz激光器的关键元器件之一,对激光器的输出功率和光束质量至关重要.研究完善了复合型金属网栅耦合输出镜的理论模型,提出反射率,透射率和损耗的计算和评估方法.设计并制作出2.52 THz波段,反射率透射率为(70%/11%)和(87%/4%)的两种耦合输出镜,对CO2泵浦激光的反射率达95 %以上.为大功率光泵THz激光器的开发提供了理论和技术支持.

As one of the key components of high-power optically pumped THz laser, hybrid metal-mesh output coupler is critical for the output power and the beam quality. A model for the hybrid metal-mesh output coupler has been developed. The reflectance, transmittance and loss of the coupler was evaluated. Output couplers at 2.52 THz have been fabricated. The reflectance and transmittance are 70% and 11% for type I, 87% and 4% for type Ⅱ.The coupler can sustain high-power CO2 laser pump with the reflectivity over 95 %. This research provides theoretical and technical supports for developing high-power optically pumped THz laser.