利用连续运转二氧化碳激光器的9R(22)输出谱线泵浦重水气体(D2 O)分子 可以产生波长为385 μm,频率为0.78 THz的连续激光辐射输出, 采用半经典理论分析方法并结合三能级系统模型可以对此激光过程进行有效的分析,通过合理近 似简化了求解过程,得到了光场中太赫兹激光信号增益系数Gs和泵浦光信号吸收系数Gp的解析表达式, 通过对求解结果的分析,计算出产生THz激光振荡的泵浦阈值条件为6.24×10－3 W/mm2。一般情况下, 在泵浦激光输出光斑面积为0.25 mm2时,要求泵浦激光谱线的输出功率达到1.6 mW以上才能形成THz激光辐射。

Pumping heavy water gas (D2 O) molecules using continuous operation carbon dioxide laser 9R(22) output line, continuous terahertz laser radiation output with 385 μm wavelength and 0.78 THz frequency can be produced. The laser process can be effectively analyzed with the semi-classical theory analysis method combining three level system model, and the solving process was simplified through reasonable approximation. The analytical expressions of terahertz laser signal gain coefficient Gs and pump light signal absorption coefficient Gp were obtained, and the pump threshold for producing terahertz laser oscillation was calculated to be 6.24×10－3 W/mm2. Normally, when the pump laser output spot area is 0.25 mm2, the output power of its 9R(22) spectral line needs to be above 1.6 mW for stimulating terahertz laser radiation.