激光冷却铯原子喷泉频标的黑体辐射频移  

Frequency Shift Due to Blackbody Radiation in the Laser Cooled Cesium Fountain Frequency Standard

作　　者：高卫[1] 柯熙政[2] 刘海峰[2] 

机构地区：[1]中国科学院上海光学精密机械研究所量子光学开放实验室,上海2018002 [2]中国科学院陕西天文台,西安710600

出　　处：《光学学报》2000年第3期289-295,共7页Acta Optica Sinica

基　　金：国家科技部资助课题!(95- Yu- 34);国家自然科学基金!(1 98340 60 )

摘　　要：研究了激光冷却铯原子喷泉频标的黑体辐射频移 (包括黑体辐射塞曼频移和黑体辐射斯塔克频移 ) ,推导了频移的计算公式 ,估算了室温下频移及其不确定度的大小 ,分析了黑体辐射频移对频标准确度的影响。结果表明 :1 )室温下黑体辐射塞曼频移可达 1 0 -1 5 量级 ,在评定铯原子喷泉频标准确度时 ,需要对此项频移加以修正 ;2 )在利用直流斯塔克效应估算黑体辐射斯塔克频移时 ,由直流极化率常数κ的测量误差导致的黑体辐射斯塔克频移的修正误差约为 4× 1 0 -1 6,是黑体辐射斯塔克频移的主要误差来源。此项频移误差是决定铯原子喷泉频标准确度总体水平的主要因素之一。最后还提出建议 ,通过设计更精密的测量铯原子超精细跃迁直流斯塔克频移的实验以提高直流极化率常数κ的测量准确度 。The shift of the cesium hyperfine transition frequency due to blackbody radiation is investigated. The formulas for calculating the shift are derived, and the shift as well as the uncertainty at room temperature is evaluated. In addition, the effect of the frequency shift due to blackbody radiation on the accuracy of the laser cooled cesium fountain frequency standard is analyzed. Blackbody ac Zeeman shift at room temperature is calculated to be of 10 -15 order, thus should be corrected for the cesium fountain frequency standard in determining the accuracy of the standard. When the blackbody ac Stark shift of cesium hyperfine transition is evaluated by determining the dc Stark effect, the uncertainty in the determination of 133 Cs dc hyperfine polarizability constant κ will bring out a fractional frequency uncertainty of about 4×10 -16 to the correction of blackbody ac Stark shift. This uncertainty is one of the critical factors governing the accuracy level of the cesium fountain frequency standard. In this connection, more precise experiments to determine 133 Cs dc hyperfine Stark shift are desirable.

关 键 词：激光冷却 铯原子喷泉频标 黑体辐射 频移 

分 类 号：O562.1[理学—原子与分子物理] O431[理学—物理]