NIM的微波-光學頻率基準研究——復現米和秒定義

李天初

中國計量科學研究院（NIM）,北京100013

摘　要:報道中國計量科學研究院（NIM）在微波一光學頻率計量研究的新進展：用NIM4激光冷卻-銫原子噴泉鐘復現國際單位制（SI）時間單位秒（s），用飛秒（FS）光學頻率梳間接復現長度單位米（m）并標定穩頻激光波長實際實施米定義。NIM4銫原子噴泉鐘的不確定度達到5×10^-15，飛秒（FS）光梳鎖定到NIM4鐘控制的氫鐘后，其頻率不確定度為2．2×10^-14。在此基礎上討論銫原子噴泉鐘、穩頻激光、FS光梳的作用、意義和相互關系。最后簡要介紹NIM5銫原子噴泉鐘的研究進展和2006年起NIM立題研制鍶原子存儲光鐘。[著者文摘]

關鍵詞:計量 頻率基準 穩頻激光 銫原子噴泉鐘 飛秒光梳

Microwave- Optical Frequency Standards at NIM： Realizing of Definition of Metre and SecondLi Tianchu National Institute of Metrology （ NIM ） , Beijing 100013, ChinaAbstract:The paper presents the realization, at NIM, of SI time unit second using the NIM4 cesium fountain clock, SI length unit meter using a femto-second （FS） optical frequency comb and calibration of wavelengths of stabilized lasers by this FS comb. The uncertainty of NIM4 fountain clock was evaluated as 5 × 10^15. The frequency uncertainty of the FS optical comb locked to a H-maser, which is steered by NIM4 clock, was estimated as 2.2 × 10^- 14 The function, significance of Cs fountain clock, stabilized lasers, optical comb and relationship among them are discussed. Finally the progress of NIM5 fountain clock and the construction of a Sr atom optical clock started in 2006 at NIM are reported.[著者文摘]

Key words:metrolo; frequency standard; stabilized laser; Cs fountain clock; FS optical comb