Optical-pumping small caesium clock based on modulation transfer spectrum frequency stabilizing laser

Abstract

The invention discloses an optical-pumping small caesium clock based on modulation transfer spectrum frequency stabilizing laser. Narrow-linewidth laser of modulation transfer spectrum frequency stabilization of high frequency stabilization degree serves as pumping laser and detection laser. A narrow linewidth laser, first to fifth half-wave plates, first to fifth polarization splitting prisms, aphase modulator, a caesium atom bubble with a magnetic shielding and heating thermal insulation material, a high-speed photoelectric detector, a laser phase demodulation and high speed servo control circuit, a laser driving power supply, an acousto-optic modulator, a atomic beam tube, a fluorescence detector, a microwave signal source, and a clock phase demodulation and servo control circuit are included. According to the provided high-performance optical pumping small caesium clock, the transition spectral line signal to noise ratio and frequency stabilization degree of the clock can be obviously enhanced, and influence of light frequency shift is reduced.

Description

technical field [0001] The invention belongs to the technical field of microwave atomic clocks and microwave quantum frequency standards, in particular to an optically pumped small cesium clock microwave quantum frequency standard using modulation shift spectrum frequency stabilized high-performance narrow-linewidth lasers as pumping lasers and detection lasers and its Preparation. Background technique [0002] As a primary frequency standard, miniaturized cesium atomic microwave clocks (small cesium clocks) have been widely used in the fields of punctuality and timing, positioning and navigation, time synchronization, and deep space exploration. It plays a pivotal role in the field of quantum frequency standard technology. Frequency stability is an important or even the most important index to measure the performance of atomic clocks, especially for application-oriented optically pumped small cesium clocks. The frequency stability of optically pumped small cesium clocks dep...

AI Technical Summary

Problems solved by technology

[0003] At present, lasers with wide linewidths such as DBR and DFB are usually used in the world, combined with frequency stabilization techniques such as saturated absorption spectroscopy or polarization spectroscopy, and the frequency-stabilized laser is used as the pumping laser and detection laser for optically pumping small cesium clocks. , but this kind of laser with wide linewidth up to several megahertz will introduce frequency noise and derived intensity noise to the clock system, which limits the improvement of the signal-to-noise ratio of the clock transition line

In addition, the saturable absorption spectrum frequency stabilization technology usually requires internal modulation of the laser, which will also introduce additional frequency noise, and the frequency stability of the frequency-stabilized laser is limited by the bandwidth of the feedback loop and the residual Doppler background; polarization spectrum stabilization The frequency technology also has the problem of locking the reference zero point as the optical power and other parameters change. At the same time, the frequency stabilization technology is also limited by the bandwidth of the feedback loop; so the laser and frequency stabilization technology commonly used at present limit the frequency stability of optically pumped small cesium clocks. Further improvements in accuracy and frequency accuracy metrics

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