基于Rb^(87)调制转移光谱稳频技术研究  

Research on Frequency Stabilization Technology of Modulation Transfer Spectroscopy Based on Rb^(87)

作　　者：洪毅[1,2] 侯霞 陈迪俊[1,3] 周翠芸[1] 黄敏捷 宋铁强[1] 王桂冰[1] 赵剑 陈卫标 Hong Yi;Hou Xia;Chen Dijun;Zhou Cuiyun;Huang Minjie;Song Tieqiang;Wang Guibing;Zhao Jian;Chen Weibiao(Spaceborne Laser Engineering Department,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,,Shanghai 201800,China;University of Chinese Academy of Sciences,Hangzhou Institute for Advanced Study,University of Chinese Academy of Sciences,Beijing 100049,China;Hangzhou Institute for Advanced Study,University of Chinese Academy of Sciences,Hangzhou,Zhejiang 310024,China)

机构地区：[1]中国科学院上海光学精密机械研究所航天激光工程部,上海201800 [2]中国科学院大学,北京100049 [3]国科大杭州高等研究院,浙江杭州310024

出　　处：《中国激光》2021年第21期21-28,共8页Chinese Journal of Lasers

摘　　要：相对于传统的780 nm饱和吸收光谱稳频技术,调制转移光谱法具有更高的灵敏度和分辨率。采用调制转移光谱技术将1560 nm分布式反馈激光器经全光纤放大和PPLN晶体高效倍频至780 nm后锁定在Rb^(87)原子D_(2)线超精细谱线5^(2)S_(1/2)(F_(g)=1)→5^(2)P_(3/2)(F_(e)=0,1)交叉共振峰上,20 h激光器的频率漂移峰峰值为105 kHz,1 s的阿伦方差为3.7×10^(-11),10000 s的阿伦方差为4.6×10^(-12)。研究了铷泡吸收长度对频率稳定性的影响。针对Rb^(87)5^(2)S_(1/2)(F_(g)=1)→5^(2)P_(3/2)(F_(e)=0,1,2)吸收峰较弱问题,研究了不同偏振类型的泵浦光和探测光对误差信号的影响。Objective Compared with the traditional 780 nm saturated absorption spectroscopy,modulation transfer spectroscopy has higher sensitivity and resolution.It is very suitable for laser frequency stabilization.Nowadays,most of the researchers focus their attention on the hyperfine D_(2)line 5^(2)S_(1/2)(F_(g)=2)→5^(2)P_(3/2)(F_(e)=3)of Rb^(87)modulation transfer spectrum frequency stabilization technology.However,there are few reports on the hyperfine D_(2)line 5^(2)S_(1/2)(F_(g)=1)→5^(2)P_(3/2)(F_(e)=0,1,2).The main reason is that the saturation absorption peak and error signal amplitude of the latter are much smaller than the former.But the frequency of hyperfine D_(2)line 5^(2)_(S1/2)(F_(g)=1)→5^(2)P_(3/2)(F_(e)=0,1)cross resonance peak of Rb^(87),which is suitable for the re-pumping laser needed by cold atomic clock system to cool rubidium atoms,has great research significance.Therefore,it is necessary for us to study it.Methods By main oscillator power amplifier and efficient frequency doubling of 1560 nm distributed feedback laser with a periodically poled lithium niobate(PPLN)crystal,we have obtained a 780 nm laser about 200 mW.We mix the modulated probe laser with the local signal and get the error signal of modulation transfer spectrum.In order to get better signal-noise ratio(SNR),the signal is amplified and passed by a low-pass-filter.We also change the modulation frequency and modulation depth of electro-optic modulator(EOM)to increase the amplitude of the error signal.The laser frequency is locked to the D_(2)hyperfine transition 5^(2)S_(1/2)(Fg=1)→5^(2)P_(3/2)(Fe=0,1)of Rb^(87)via proportional-integral-derivative(PID)controller and we get a 20 h laser frequency stability data finally.We change the polarization of probe laser and pump laser by adjusting the optical structure,so as to study the influence of different polarization states on the error signal of modulation transfer spectrum.By changing the absorption length of rubidium cell(25 mm and 50 mm),we study its effect on laser frequency stab

关 键 词：激光光学 激光稳频 调制转移光谱技术 反馈光 偏振 超冷原子 

分 类 号：TN249[电子电信—物理电子学]