建立了用于测量钠原子光谱的无多普勒饱和荧光光谱测量系统。在该系统中使用了线宽约100 kHz的窄线宽染料激光器和光电二极管探测器。钠泡温度控制在65 ℃。两束相向传播的激光束在钠泡中重叠共同激发荧光。光电二极管被放置在钠泡的侧面接收、探测激发的荧光。LabVIEW软件控制的数据采集卡采集光电二极管的信号。通过扫描染料激光器的激光频率,可以观测到钠原子的无多普勒特征D2a,交叉共振以及D2b。当激光频率扫描的步长约为2 MHz时,在实验中观测到了D2a中的三条谱线。

The Doppler-free saturation fluorescence spectra system is set up. 100 kHz narrow-band dye laser and photodiode are used in this system. Two counterpropagating dye laser beams overlap on a Na cell whose temperature is set at 65 ℃. And a photodiode located at one side of the Na cell collects and detects the excited fluorescence. Then photodiode signal is sampled by data acquisition card which is controlled by LabVIEW software. Doppler-free features D2a,crossover and D2b are observed by scanning the dye laser frequency. When the dye laser frequency scan step is about 2 MHz,three lines in the D2a can be observed in this experiment.