Coherent Population Beat Atomic Clock with Synchronous Coherent Light Field Excitation and Its Realization Method

Abstract

The present invention discloses a CPB atomic clock of synchronization coherent light field excitation and a realization method thereof. The laser of the atomic clock comprises an excitation laser and a detection laser which are respectively to generate coherent excitation laser and coherent detection laser; local oscillation signals generated by a local oscillator pass through a frequency integration system to obtain microwave signals near the atom ground state energy level transition frequency, and a modulation laser generates two coherent laser modes; detection and excitation light beams are acted to an atom air chamber at the same, and the light beam is superposed in the atom air chamber; and the detection laser permeating the atom air chamber is received by a photoelectric detector and is subjected to continuous excitation and continuous detection at the same time to obtain continuously undamped CPB oscillation signals and obtain the central frequency through frequency analysis, and the frequency drift is subjected to compensation to obtain the atom transition frequency and output frequency signals for the fiducial standard. The problem is solved that CPB oscillation signals are rapidly reduced with the time, and the measurement accuracy and the CPB atom clock stability level are improved.

Description

technical field [0001] The invention relates to a coherent population beat frequency atomic clock, in particular to a coherent population beat frequency atomic clock excited by a synchronous coherent light field and a realization method thereof. Background technique [0002] The coherent population beating atomic clock is a frequency direct reading atomic clock based on the coherent population beating (CPB) phenomenon. Two beams generated by a laser modulated by a microwave signal are locked to atomic transition frequencies with a certain frequency difference ω 21 The coherent light incident on the atomic gas cell, when ω 21 and atomic ground state hyperfine splitting frequency Δ 21 When equal, the atom will be trapped in the two ground state energy levels, no longer absorb photons and jump to the excited state, this phenomenon is called coherent population trapping (CPT). When the system is in the CPT state, if the frequency difference between two coherent light fields i...

AI Technical Summary

Problems solved by technology

The frequency spectrum of the decaying oscillation signal has a wide linewidth, which is equal to the linewidth of the CPT resonance peak, which is very unfavorable for the accurate determination of its oscillation center frequency, thus restricting the stability of the atomic clock

At the same time, this method requires repeated periodic excitation to measure

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