摘要
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.
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.
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)
