An optical lattice clock based on 87Sr is built at National Institute of Metrology （NIM） of China. The systematic frequency shifts of the clock are evaluated with a total uncertainty of 2.3×10-16. To measure it...An optical lattice clock based on 87Sr is built at National Institute of Metrology （NIM） of China. The systematic frequency shifts of the clock are evaluated with a total uncertainty of 2.3×10-16. To measure its absolute frequency with respect to NIM＇s cesium fountain clock NIM5, the frequency of a flywheel H-maser of NIM5 is transferred to the Sr laboratory through a 50-kin-long fiber. reference frequency of this H-maser, is used for the optical this Sr clock is measured to be 429228004229873.7（1.4）Hz. A fiber optical frequency comb, phase-locked to the frequency measurement. The absolute frequency of展开更多
A clock laser based on a 30-cm-long ultrahigh finesse optical cavity was developed to improve the frequency stability of the Sr optical lattice clock at the National Institute of Metrology. Using this clock laser to p...A clock laser based on a 30-cm-long ultrahigh finesse optical cavity was developed to improve the frequency stability of the Sr optical lattice clock at the National Institute of Metrology. Using this clock laser to probe the spin-polarized87Sr atoms, a Rabi transition linewidth of 1.8 Hz was obtained with 500 ms interrogation time.Two independent digital servos are used to alternatively lock the clock laser to the 1S0（mF=＋9∕2）→3P0（mF=＋9∕2）transition. The Allan deviation shows that the short-term frequency stability is better than3.2 × 10-16and averages down followed by 1.8 × 10-15∕τ1/2.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 91336212 and 91436104
文摘An optical lattice clock based on 87Sr is built at National Institute of Metrology （NIM） of China. The systematic frequency shifts of the clock are evaluated with a total uncertainty of 2.3×10-16. To measure its absolute frequency with respect to NIM＇s cesium fountain clock NIM5, the frequency of a flywheel H-maser of NIM5 is transferred to the Sr laboratory through a 50-kin-long fiber. reference frequency of this H-maser, is used for the optical this Sr clock is measured to be 429228004229873.7（1.4）Hz. A fiber optical frequency comb, phase-locked to the frequency measurement. The absolute frequency of
基金supported by the National Key R&D Program of China(Nos.2016YFF0200201 and 2017YFA0304404)the National Natural Science Foundation of China(Nos.91336212 and 91436104)
文摘A clock laser based on a 30-cm-long ultrahigh finesse optical cavity was developed to improve the frequency stability of the Sr optical lattice clock at the National Institute of Metrology. Using this clock laser to probe the spin-polarized87Sr atoms, a Rabi transition linewidth of 1.8 Hz was obtained with 500 ms interrogation time.Two independent digital servos are used to alternatively lock the clock laser to the 1S0（mF=＋9∕2）→3P0（mF=＋9∕2）transition. The Allan deviation shows that the short-term frequency stability is better than3.2 × 10-16and averages down followed by 1.8 × 10-15∕τ1/2.
