Abstract: The mercury ion trapped microwave clock utilizes a quadrupole trap to achieve ion trapping,and completes the preparation of mercury ion states through a mercury lamp,making it easy to integrate and miniaturize.Through the optimization and design of key components such as ion trap,mercury lamp and its optical path,the pump light emitted by the mercury lamp can fully interact with the ions trapped in the ion trap to complete the preparation of states.40.5 GHz microwave is transmitted to the center of the ion trap through the horn antenna to complete the inversion of the ion number.The transiting line of the trapped mercury ions is detected by a weak fluorescence detection system and the measured transiting line width is about 1 Hz.The closed-loop locking of mercury ion microwave clock is achieved by the servo loop control system.After experiment testing,the frequency stability index can reach 4E-13/τ(1 s≤τ≤1 000 s) and 7E-15 at 10 000 s.

Key words: Mercury ion trapped microwave frequency standard, Ion trap, Mercury lamp