Recipe of Rb Atomic Clock

白丽娜, 曹远洪, 刘类骥 +3 more

Li-Na Bai, Yuanhong Cao, Leiji Liu +3 more

We introduce a novel waveguide cavity for ultra-miniature cell-type Rb atomic clock. In the cavity, a coupling ring shaped to be a semi-circle imports an rf signal from electronics, a screw regulator acts as a medium coupler to transmit the microwave signal into the absorption cell, and both the parts serve as a filter to suppress useless components except 6.8 GHz. Furthermore, the waveguide cavity can be used to design a miniature Rb atomic clock, and spread it to a chip-scale atomic clock. We have completed the design of the smallest cell-type Rb atomic clock in the world based on this waveguide cavity. It has not only a small size but also obviously better key performances than those of other miniature Rb atomic clocks. This ultra-miniature cell-type Rb atomic clock aging is 4 × 10 −13 /d, which is obviously slower than that of other miniature Rb atomic clocks.

Lu Liu, Guo Tao, Ke Deng +3 more

An atomic clock system based on coherent population trapping (CPT) resonance in 85 Rb is reported, while most past works about the CPT clock are in 87 Rb. A new modulation method (full-hyperfine-frequency-splitting modulation) is presented to reduce the effect of light shift to improve the frequency stability of the CPT clock in 85 Rb. The experimental results show that the short-term frequency stability of the CPT clock in 85 Rb is in the order of 10 −10 /s and the long-term frequency stability can achieve 1.5 × 10 −11 /80000 s, which performs as well as 87 Rb in CPT resonance. This very good frequency stability performance associated with the low-cost and low-power properties of 85 Rb indicates that an atomic clock based on CPT in 85 Rb should be a promising candidate for making the chip scale atomic clock.

Ray LaPierre

Qiang Hao, Shaojie Yang, Peter Yun +3 more

Rb atomic clock refers to the microwave transition of87Rb atoms, generally considered as a low-cost and low-performance atomic frequency standard. The maturity of semiconductor laser offers us a new opportunity to improve the Rb atomic clock. However, there are also many challenges in terms of electronic system and optical bench. Despite the performance superiority of the pulsed optically pumped (POP) Rb atomic clock has been demonstrated in the laboratory, there still no integrated prototype emerges to date. Here, we report the design and characteristics of an integrated POP Rb atomic clock. The primary test shows short-term stability of 3.2×10-13τ-1/2(1-1000s) and 4000s frequency stability of 8.5×10-15in air. The size and power consumption are 23 L and 45 W, respectively.