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(wěn)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(wěn)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(wěn)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 |
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