通过铯原子D_1线超精细跃迁能级的偏振光谱获得鉴频曲线,利用电子伺服系统将鉴频曲线反馈到894.6nm外腔式半导体激光器的压电陶瓷上进行锁定。由于偏振光谱技术不需要对激光器进行调制,因此不会带来额外的噪声。激光器自由运转400s内频率起伏为2.35 MHz,采用偏振光谱锁定激光器后400s内频率起伏为0.95 MHz,有效抑制了激光器的频率起伏。
The laser is locked on the transition F=4→F′=3 of ~(133)Cs D_1 line when using polarization spectroscopy technology,in which the polarization spectroscopy as the error signal negatively gives feedback to the electronic servo-system.The frequency stabilization technology does not bring extra frequency noise because it's a modulation-free frequency locking scheme.The frequency fluctuation is 0.95 MHz in 400 swhen the laser is locked,while it is 2.35 MHz for free running.