光学学报, 2009, 29 (2): 425, 网络出版: 2009-02-23
采用偏振光谱对外腔半导体激光器稳频时反馈环路带宽的影响 下载: 659次
Influence of the Bandwidth of Feedback Loop in Frequency Stabilization of External-Cavity Diode Laser by Polarization Spectroscopy
外腔半导体激光器 偏振光谱 稳频 反馈环路带宽 单原子磁光阱 external-cavity diode laser (ECDL) polarization spectroscopy laser frequency stabilization bandwidth of feedback loop single-atom magneto-optical trap
摘要
在采用磁光阱实现单个铯原子俘获的实验中, 运用无调制偏振光谱方法将光栅外腔半导体激光器(提供冷却/俘获光)的频率锁定在铯原子6S1/2 F=4→6P3/2 F′=5的超精细跃迁线上。采用偏振光谱技术得到的类色散曲线作为鉴频信号, 并同时对光栅外腔半导体激光器的电流调制端口和光栅外腔的压电陶瓷电压调制端口进行反馈, 以拓展反馈环路的带宽, 实现激光器的频率锁定。与通常的饱和吸收光谱稳频技术相比, 激光频率锁定之后的频率稳定度得到了明显改善。在取样时间τ=300 s时, 阿仑方差σy(τ)=4.6×10-12。
Abstract
Based on the experiment of trapping single cesium atoms in magneto-optical trap (MOT), a grating-external-cavity diode laser, which provides the cooling/trapping beams of MOT is locked to cesium 6S1/2 F=4→6P3/2 F′=5 cycling transition by modulation-free polarization spectroscopy. This frequency locking method uses the dispersion-like curve generated from polarization spectroscopy as frequency-discriminating signal. The error signal is feedback to both current modulation port of diode laser and voltage modulation port of piezoelectric transducer (PZT) in grating external cavity. The locking technique of modulation-free polarization spectroscopy can clearly improve the frequency stability compared with conventional saturation absorption spectroscopic technique. The minimum value of Allan variance is σy(τ) = 4.6×10-12 at average time of τ=300 s.
王婧, 杨保东, 何军, 赵江艳, 张天才, 王军民. 采用偏振光谱对外腔半导体激光器稳频时反馈环路带宽的影响[J]. 光学学报, 2009, 29(2): 425. Wang Jing, Yang Baodong, He Jun, Zhao Jiangyan, Zhang Tiancai, Wang Junmin. Influence of the Bandwidth of Feedback Loop in Frequency Stabilization of External-Cavity Diode Laser by Polarization Spectroscopy[J]. Acta Optica Sinica, 2009, 29(2): 425.